Identification and characterization ofugpErequired for the full virulence of Streptococcus suis

Identification and characterization of ugpE required for the full virulence of Streptococcus suis | bioRxiv /* */ /* */ <!-- <!-- /*! * yepnope1.5.4 * (c) WTFPL, GPLv2 */ (function(a,b,c){function d(a){return"[object Function]"==o.call(a)}function e(a){return"string"==typeof a}function f(){}function g(a){return!a||"loaded"==a||"complete"==a||"uninitialized"==a}function h(){var a=p.shift();q=1,a?a.t?m(function(){("c"==a.t?B.injectCss:B.injectJs)(a.s,0,a.a,a.x,a.e,1)},0):(a(),h()):q=0}function i(a,c,d,e,f,i,j){function k(b){if(!o&&g(l.readyState)&&(u.r=o=1,!q&&h(),l.onload=l.onreadystatechange=null,b)){"img"!=a&&m(function(){t.removeChild(l)},50);for(var d in y[c])y[c].hasOwnProperty(d)&&y[c][d].onload()}}var j=j||B.errorTimeout,l=b.createElement(a),o=0,r=0,u={t:d,s:c,e:f,a:i,x:j};1===y[c]&&(r=1,y[c]=[]),"object"==a?l.data=c:(l.src=c,l.type=a),l.width=l.height="0",l.onerror=l.onload=l.onreadystatechange=function(){k.call(this,r)},p.splice(e,0,u),"img"!=a&&(r||2===y[c]?(t.insertBefore(l,s?null:n),m(k,j)):y[c].push(l))}function j(a,b,c,d,f){return q=0,b=b||"j",e(a)?i("c"==b?v:u,a,b,this.i++,c,d,f):(p.splice(this.i++,0,a),1==p.length&&h()),this}function k(){var a=B;return a.loader={load:j,i:0},a}var l=b.documentElement,m=a.setTimeout,n=b.getElementsByTagName("script")[0],o={}.toString,p=[],q=0,r="MozAppearance"in l.style,s=r&&!!b.createRange().compareNode,t=s?l:n.parentNode,l=a.opera&&"[object Opera]"==o.call(a.opera),l=!!b.attachEvent&&!l,u=r?"object":l?"script":"img",v=l?"script":u,w=Array.isArray||function(a){return"[object Array]"==o.call(a)},x=[],y={},z={timeout:function(a,b){return b.length&&(a.timeout=b[0]),a}},A,B;B=function(a){function b(a){var a=a.split("!"),b=x.length,c=a.pop(),d=a.length,c={url:c,origUrl:c,prefixes:a},e,f,g;for(f=0;f<d;f++)g=a[f].split("="),(e=z[g.shift()])&&(c=e(c,g));for(f=0;f<b;f++)c=x[f](c);return c}function g(a,e,f,g,h){var i=b(a),j=i.autoCallback;i.url.split(".").pop().split("?").shift(),i.bypass||(e&&(e=d(e)?e:e[a]||e[g]||e[a.split("/").pop().split("?")[0]]),i.instead?i.instead(a,e,f,g,h):(y[i.url]?i.noexec=!0:y[i.url]=1,f.load(i.url,i.forceCSS||!i.forceJS&&"css"==i.url.split(".").pop().split("?").shift()?"c":c,i.noexec,i.attrs,i.timeout),(d(e)||d(j))&&f.load(function(){k(),e&&e(i.origUrl,h,g),j&&j(i.origUrl,h,g),y[i.url]=2})))}function h(a,b){function c(a,c){if(a){if(e(a))c||(j=function(){var a=[].slice.call(arguments);k.apply(this,a),l()}),g(a,j,b,0,h);else if(Object(a)===a)for(n in m=function(){var b=0,c;for(c in a)a.hasOwnProperty(c)&&b++;return b}(),a)a.hasOwnProperty(n)&&(!c&&!--m&&(d(j)?j=function(){var a=[].slice.call(arguments);k.apply(this,a),l()}:j[n]=function(a){return function(){var b=[].slice.call(arguments);a&&a.apply(this,b),l()}}(k[n])),g(a[n],j,b,n,h))}else!c&&l()}var h=!!a.test,i=a.load||a.both,j=a.callback||f,k=j,l=a.complete||f,m,n;c(h?a.yep:a.nope,!!i),i&&c(i)}var i,j,l=this.yepnope.loader;if(e(a))g(a,0,l,0);else if(w(a))for(i=0;i (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0];var j=d.createElement(s);var dl=l!='dataLayer'?'&l='+l:'';j.src='//www.googletagmanager.com/gtm.js?id='+i+dl;j.type='text/javascript';j.async=true;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-M677548'); Skip to main content Home About Submit ALERTS / RSS Search for this keyword Advanced Search New Results Identification and characterization of ugpE required for the full virulence of Streptococcus suis Qiulei Yang , Na Li , Yanyan Tian , Qiao Liang , Miaomiao Zhao , Hong Chu , Yan Gong , Tong Wu , Shaopeng Wei , He Wang , Guangmou Yan , Fengyang Li , Liancheng Lei doi: https://doi.org/10.1101/2024.09.25.615082 Qiulei Yang a State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University , Changchun, China Find this author on Google Scholar Find this author on PubMed Search for this author on this site Na Li a State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University , Changchun, China Find this author on Google Scholar Find this author on PubMed Search for this author on this site Yanyan Tian a State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University , Changchun, China Find this author on Google Scholar Find this author on PubMed Search for this author on this site Qiao Liang b Department of First Hospital, Jilin University , Changchun, China Find this author on Google Scholar Find this author on PubMed Search for this author on this site Miaomiao Zhao c College of Animal Science, Yangtze University , Jingzhou, China Find this author on Google Scholar Find this author on PubMed Search for this author on this site Hong Chu a State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University , Changchun, China Find this author on Google Scholar Find this author on PubMed Search for this author on this site Yan Gong a State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University , Changchun, China Find this author on Google Scholar Find this author on PubMed Search for this author on this site Tong Wu a State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University , Changchun, China Find this author on Google Scholar Find this author on PubMed Search for this author on this site Shaopeng Wei a State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University , Changchun, China Find this author on Google Scholar Find this author on PubMed Search for this author on this site He Wang d Department of Rehabilitation, The Second Hospital of Jilin University , Changchun, China Find this author on Google Scholar Find this author on PubMed Search for this author on this site Guangmou Yan a State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University , Changchun, China Find this author on Google Scholar Find this author on PubMed Search for this author on this site Fengyang Li a State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University , Changchun, China Find this author on Google Scholar Find this author on PubMed Search for this author on this site For correspondence: fengyangli{at}jlu.edu.cn leiliancheng{at}163.com Liancheng Lei a State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, and College of Veterinary Medicine, Jilin University , Changchun, China c College of Animal Science, Yangtze University , Jingzhou, China Find this author on Google Scholar Find this author on PubMed Search for this author on this site For correspondence: fengyangli{at}jlu.edu.cn leiliancheng{at}163.com Abstract Full Text Info/History Metrics Data/Code Preview PDF ABSTRACT Streptococcus suis ( S. suis ) is an emerging zoonotic pathogen that threatens both animal and human health worldwide. UgpE is a protein subunit of the Ugp ( u ptake of g lycerol p hosphate) transporter system that is involved in glycerophospholipid synthesis in bacterial membranes. In this study, an ugpE deletion mutant was constructed and the effects of ugpE deletion on cell morphology, biofilm formation, and virulence were investigated. Deletion of ugpE did not affect bacterial growth but impaired cell chain formation and capsular synthesis by downregulating the mRNA levels of the capsular regulon genes cps-2B , cps-2C , and cps-2S . Deletion of ugpE also led to decreased tolerance to heat, oxidative, and acid-base stress. Crystal violet staining and scanning electron microscopy demonstrated ugpE negatively regulated biofilm formation in liquid culture and the rdar biofilm morphotype on agar plates. Moreover, ugpE deletion not only reduced hemolysin activity, survival in whole human blood, and anti-phagocytosis ability against porcine alveolar macrophages (PAM) but also enhanced bacterial adhesion and invasion of human cerebral microvascular endothelial cells (hCMEC/D3) by upregulating the expression of multiple genes associated with cell adhesion. In a mouse infection model, ugpE deletion significantly attenuated virulence and lowered the number of viable bacteria in the blood and major organs, as well as distribution of macrophages. In conclusion, this study identified UgpE as a novel virulence factor that plays a pivotal role in the regulation of virulence and biofilm formation of S. suis . Introduction Streptococcus suis ( S. suis ) is an important zoonotic pathogen that causes meningitis, septicemia, endocarditis, arthritis, and pneumonia in pigs, leading to huge economic losses to the pig industry. S. suis also infects humans through direct contact with pathogen-harboring droplets or wounds, causing diseases such as meningitis and toxic shock syndrome (STSS) that threaten human health. S. suis is classified into 29 serotypes (1-34, 1/2) according to its capsule antigen, among which S. suis serotype 2 (SS2) is the most prevalent and pathogenic strain in many countries, including China, Canada, and Brazil [ 1 , 2 ]. In 1998 and 2005, outbreaks of human SS2 infection resulted in dozens of deaths in China [ 3 ]. In addition, SS2 has become the main pathogen causing meningitis in adults in southeast Asian countries and regions such as Vietnam, Thailand and Hong Kong [ 4 , 5 , 6 ]. The pathogenicity of S. suis depends on its virulence factor. To date, a variety of S. suis virulence factors have been identified, including capsular polysaccharide (CPS) [ 7 ], extracellular factor (EF) [ 8 ], muramidase-released protein (MRP) [ 9 ], suilysin (SLY) [ 10 ], glutamate dehydrogenase (GDH) [ 11 ], and fibronectin-binding protein (FbpS) [ 12 , 13 ]. However, some experimental results indicate that the absence of one or more of these virulence factors does not significantly affect the virulence of certain S. suis strains, suggesting that some of these virulence factors may act synergistically in pathogenicity or that new virulence factors may be discovered. Therefore, there are still many unsolved aspects of the pathogenesis of S. suis that need to be further investigated to better prevent and control its associated diseases with S. suis . ATP-binding cassette (ABC) transporters constitute a ubiquitous superfamily of integral membrane proteins that are responsible for the ATP-powered translocation of many substrates across membranes. Thus, they play vital roles in the regulation of a variety of physiological processes, including nutrient uptake, drug resistance, lipid transport, and the secretion of non-classical signaling molecules [ 14 ]. In prokaryotes, ABC transporters can take up nutrients, efflux toxins, and drugs, thereby affecting bacterial growth and enabling bacteria to resist various antibiotics. In addition, they play an important role in the interactions between pathogens and hosts. They are regarded as virulence factors in uropathogenic Escherichia coli because of their critical role in pathogenesis [ 15 ]. In Streptococcus pneumoniae , the ABC transporter BacA is required for the maintenance of chronic infections in mice [ 16 ]. In S. suis , proteome analysis has identified genes encoding diverse ABC transporters that may play roles in colonization and infection processes [ 17 , 18 , 19 , 20 ]. Moreover, the ABC transporter component ATPase MsmK regulates the pathogenicity of S. suis by utilizing carbohydrates [ 21 ]. ABC transporters are also involved in the regulation of biofilm formation in various streptococci [ 22 ]. The uptake of glycerol phosphate (Ugp) system belongs to the ABC transporter superfamily and is involved in glycerophospholipid synthesis by uptake of sn -glycerol-3-phosphate (G3P) and certain glycerophosphodiesters from the periplasm to the cytosol in E. coli [ 23 ]. The Ugp transporter consists of four subunits known as the UgpABCE system, of which UgpA and UgpE constitute the transmembrane domains, UgpC forms a homodimer of the ATP-hydrolyzing subunit, and UgpB is a periplasmic substrate-binding protein [ 24 ]. In addition to glycerophospholipid synthesis, Ugp transporters are also involved in the regulation of other cellular functions by the uptake of G3P and glycerophosphodiesters. Glycerophosphodiesters serve as an osmoprotectant in eukaryotic cells [ 25 , 26 , 27 ]. Moreover, glycerophospholipids are required for the normal growth and virulence of Mycoplasma pneumoniae [ 28 , 29 ]. However, the role of Ugp transporters in the regulation of virulence in other bacterial species remains unknown. In this study, we assessed the role of ugpE (gene ID: YP_003028379.1), a homologous gene that encodes the Ugp transporter subunit UgpE (protein ID: ARL70172.1), in the regulation of various cellular phenotypes, including growth, stress tolerance, biofilm formation, and virulence of the zoonotic pathogen SS2. Our study contributes to elucidating the molecular mechanisms underlying the pathogenesis of S. suis and to the development of novel therapies and vaccines against diseases caused by S. suis . Materials and methods Bacterial strains and culture conditions All strains used in this study are listed in Table S1. SS2 strain SC19 was kindly provided by Prof. Anding Zhang (Huazhong Agricultural University, Wuhan, China). Bacterial cultures were performed under different conditions according to the experimental requirements. SS2 and its derivatives were cultivated in Todd-Hewitt broth (THB; Hopebio, HB0311-3) or plated on THB agar plates supplemented with kanamycin (100□µg/mL; Beyotime, ST101) and spectinomycin (100□µg/mL; Macklin, S6106), if relevant. E. coli strain DH5α was cultured in Luria-Bertani (LB; Becton Dickinson, DF0446-17-3) liquid medium or on LB agar plates containing 100□µg/mL spectinomycin if relevant. Construction of mutant and complemented strains The ugpE chromosomal deletion mutant was constructed by homologous recombination as previously reported [ 30 ]. Briefly, the upstream and downstream homologous regions of ugpE were amplified using the A1/A2 and A3/A4 primer pairs, resulting in two fragments that were fused and ligated into the pSET4s shuttle vector [ 31 ]. The recombinant plasmid was electroporated into SC19 cells, and the bacteria were selected on THB agar plates supplemented with 100 μg/mL spectinomycin at 37°C. The mutant strains (Δ ugpE ) were confirmed by spectinomycin susceptibility tests and PCR, using the primer pair A5/A6. Gene complementation was conducted by cloning ugpE into the pSET2 shuttle vector [ 31 ] using primer Y1/Y2, which contains a putative promoter region. The inserted DNA sequences were confirmed using PCR and DNA sequencing. The recombinant plasmid was electroporated into the mutant strain to produce the complementary strain CΔ ugpE . The primers and plasmids used are listed in Tables S1 and S2, respectively. Growth curves Briefly, S. suis (WT, Δ ugpE , and CΔ ugpE ) cells were cultured overnight, diluted 1:100, and grown to the exponential phase in THB (with 10% FBS). The bacteria were diluted in THB again at 1:100 dilution and incubated at 37°C under vigorous shaking at 180 rpm. The OD 600 value was measured every hour for 10 h. Growth curves were plotted using GraphPad Prism (version 9.0; San Diego, CA, USA). Observation of colony morphology The bacterial chain length and capsule were observed using light and transmission electron microscopy (TEM), respectively. Briefly, a suspension of bacterial cells (WT, Δ ugpE , CΔ ugpE ) grown overnight was diluted in THB (with 10% FBS) medium and were diluted in THB again at 1:100 dilution and incubated at 37°C under vigorous shaking at 180 rpm. For light microscopy, the cells were harvested at the mid-log growth phase for Gram staining. The bacterial chain length was observed under a light microscope (Nikon) and determined by counting the cell numbers of 200 chains per cell. For TEM, cells in the mid-log growth phase were collected and fixed in 2.5% glutaraldehyde overnight. After dehydration with propylene oxide and embedding in epoxy resin, the samples were sectioned and stained with 1% uranyl acetate and alkaline lead citrate and observed under a Hitachi HT 7700 (Hitachi, Tokyo, Japan) electron microscope at 80□kV. The bacterial cell width, cell wall, and capsule thickness were determined using ImageJ software (version 1.8.0) by randomly selecting 20 cells. Bacterial stress tests Bacterial stress tests were performed as previously described with slight modifications [ 32 ]. Briefly, overnight cultures of S. suis cells (WT, Δ ugpE , CΔ ugpE ) were diluted in THB medium at 1:100 dilution and grown to mid-log stage at 37°C. For the hydrogen peroxide (H 2 O 2 ) test, cells were diluted again to OD 600 = 0.1 and grown to the mid-log stage. H 2 O 2 (30 mM) and PBS (control) were added to the cells and incubated at 37°C for 20 min. For the heat stress analysis, cells were also diluted to OD 600 = 0.1 and incubated at 37°C and 40°C for 12 h. For the acid tolerance test, cells were harvested after centrifugation at 4°C, washed three times with PBS (pH 7.4), and cultured with fresh THB medium at different pH values (2.0, 4.0, 6.0, 6.0, 7.0, 8.0, 10.0, and 12.0) for 45 min at 37°C. For all assays, cells were plated on THA plates after serial dilution in PBS and bacterial numbers were counted after overnight incubation. Each sample was set up in triplicate and repeated independently three times. Bacterial adhesion and invasion assays Adhesion and invasion assays were performed in the human cerebral microvascular endothelial cell line, hCMEC/D3, as described previously [ 33 ]. hCMEC/D3 cell line was kindly provided by Prof. Yan Chen (College of Life Sciences, Jilin University). Briefly, hCMEC/D3 cells were cultured to approximately 2.5 × 10 5 cells/well in a 24-well plate, followed by infection with different groups of bacteria at a multiplicity of infection (MOI) of 100:1. After incubation at 37°C and 5% CO 2 for 1 h, the cells were washed four times with PBS to remove non-adherent bacteria. For the adhesion assay, cells were lysed with 0.1% saponin. Bacterial adherence was calculated as follows: (recovered CFU/initial inoculum CFU) × 100%. For the invasion assay, cells were incubated with fresh DMEM supplemented with 5 μg/mL penicillin G (Sangon Biotech; B540729-0010) and 100 μg/mL gentamicin (Sangon Biotech; E607063-0100) for 2 h to kill non-adherent bacteria and then lysed with 0.1% saponin (Merck; 47036). Lysates were plated on THA plates after serial dilution in PBS and bacterial numbers were counted after overnight incubation. Bacterial invasion was calculated as follows: (recovered CFU/adhered CFU) × 100%. Each sample was set up in triplicate and repeated independently three times. Phagocytosis The phagocytosis assay was conducted in porcine alveolar macrophages (PAM) as described previously, with slight modifications [ 34 ]. Immortalized PAM (ATCC, CRL-2845) was provided by the Harbin Veterinary Research Institute of the Chinese Academy of Agricultural Sciences. PAM cells were cultured to approximately 2.5 × 10 5 cells/well in a 24-well plate, followed by infection with different groups of bacteria at a MOI of 40:1. After incubation at 37°C and 5% CO 2 for 1 h, the cells were washed three times with PBS and incubated with fresh DMEM supplemented with 5 μg/mL penicillin G and 100 μg/mL gentamicin for 2 h to kill non-adherent bacteria. The cells were then washed three times with PBS and lysed with trypsin (ThermoFisher; R001100). Lysed cells were serially diluted and plated on THA plates for counting. Each sample was set up in triplicate and repeated independently three times. Whole blood survival Each group of bacteria (WT, Δ ugpE , CΔ ugpE ) was cultured in THB supplemented with 1% glucose until mid-log growth phase. After centrifugation, the bacterial body was collected and resuspended to an OD 600 of 0.2 in PBS. Then, 1 mL of germ-free human whole blood containing EDTA-Na 2 anticoagulant was added to 100 μL of the bacterial samples and incubated at 37°C for 2h. The mixture was serially diluted and plated on THA plates for cell counting. Survival was calculated as follows: (recovered CFU/CFU in the original inoculum) ×100%. The experiment was repeated three times, and three samples were collected in triplicate each time. Biofilm formation Biofilm formation (adherence to the well wall) was assessed as described previously, with slight modifications [ 35 ]. Briefly, each group of bacteria (WT, Δ ugpE , CΔ ugpE ) was incubated in 96-well plates with 200 μL THB medium per well at 37°C for 24h, 48h, and 72h. After removing the unattached bacteria, adherent cells were stained with 0.2% crystal violet, washed, and dissolved in a 95% alcohol solution. Biofilms were measured as the absorbance of dissolved crystal violet at OD 595 . Rdar (red, d ry, a nd rough) morphotype assessment was performed as described previously [ 36 ]. Briefly, 5□µL of an overnight culture of OD 600 □=□5 suspended in water was spotted onto THA plates containing the dye Congo red (40□µg/mL) and Coomassie Brilliant Blue G-250 (20□µg/mL) or calcofluor white (Fluorescence Brightener 28, 50□µg/ml). After incubation at 37°C for 24h, 48h, and 72h, pictures were taken to analyze the development of the colony morphology structure and dye binding. The surface morphology of the colonies was plotted and analyzed using the ImageJ software (version 1.8.0). Scanning electron microscopy Scanning electron microscopy (SEM) was performed to visualize the macrocolony biofilms. An overnight culture of OD 600 □=□5 suspended in water was prepared and spotted on THA plates pre-embedded with a rectangular glass slide. After 48h of culture at 37°C, the macrocolonies on the glass slide were fixed in fixative solution (0.5% glutaraldehyde and 2.5% paraformaldehyde in 10□mM HEPES, pH 7.0), dehydrated with acetone, sputter-coated with gold/palladium, and observed using a Zeiss Merlin field emission SEM at an acceleration voltage of 10□kV with an Everhart-Thornley secondary emission (SE) detector. RNA isolation and qRT-PCR Each group of bacterial cells (WT, Δ ugpE , CΔ ugpE ) was grown in THB medium until the mid-log growth phase. Total RNA was extracted using TRIzol reagent (Invitrogen, USA), according to the manufacturer’s instructions. RNA was treated with DNase (Invitrogen, USA), and RNA quality was assessed by gel electrophoresis and PCR. The RNA concentration was measured using a NanoDrop 2000 system (Thermo Scientific). cDNA was synthesized using 1 μg of RNA from each sample using the Prime Scrip RT Master Mix Kit (TaKaRa, Dalian, China). Quantitative PCR (qPCR) was performed using TB Green PCR Master Mix (TaKaRa, Dalian, China) on a Quantagene q225 qPCR System (Kubo, Beijing, China). The 16S rRNA gene was used as an internal reference gene for normalization. Data were analyzed using the 2 −ΔΔCT method. All experiments were performed at least three times. The primers used are listed in Table S2. Animal experiments All animal experiments were approved by the Institutional Animal Care and Use Committee of Jilin University and were conducted in accordance with the Chinese Laboratory Animal Administration Act 1988 and the Helsinki Declaration of 1975. To determine bacterial virulence in mice, forty 6-weeks old female BALB/c mice (body weight 18 ± 2 g, purchased from Changsheng Biotechnology Co., Ltd., China) were divided into four groups (10 mice per group) randomly and intraperitoneally infected with 100 μL (1×10 9 CFU, LD 50 =5×10 8 CFU) of SC19, Δ ugpE , CΔ ugpE or PBS (as control). All mice were housed in standard plastic mouse cages and kept under constant room temperature (23 ± 3°C), humidity (55 ± 5 %), and observed for one week. Clinical scores, body weight changes, and animal deaths were recorded every 12 h. For histopathological analysis, mice were intraperitoneally infected with 100 μL (5×10 8 CFU) of each strain or PBS (as a control). After 3 days, the mice were euthanized by inhalation of CO 2 and organs including the brain, lung, liver, spleen, and kidney were extracted and frozen at −80°C or used immediately for histopathological analysis and flow cytometry. Histopathological analysis was performed as described previously [ 37 ]. Briefly, the tissues were fixed in 10% formaldehyde solution, embedded in paraffin, sliced, and stained with hematoxylin and eosin (HE). The stained sections were visualized, and pathological changes in the tissues were analyzed under an optical microscope (Olympus, Tokyo, Japan). The histological score was assessed as previously described [ 38 ]. Additionally, to evaluate the distribution of bacteria in different organs after infection, equal weights of brain, lung, liver, spleen, kidney, and blood samples were homogenized, diluted, and plated on THA plates for cell counting. Flow cytometry Macrophages in the lung, liver, spleen, heart, and kidney were assessed using flow cytometry, as previously reported [ 39 ]. Briefly, the organs were shred and digested in HBSS containing gelatinase A (100 U/mL) and DNase (20 µg/mL). After filtration and rinsing with PBS, the samples were centrifuged and the pellets were treated with ice-cold RBC lysis buffer for 5 min. The isolated cells were washed with ice-cold PBS again and centrifuged to collect the cell pellets for antibody labeling in a fluorescent washing buffer (Thermo Fisher). The cell suspension was incubated with BV421 anti-mouse CD11b, APC anti-mouse F4_80, PE anti-mouse CD206, PE-Cy5.5 anti-mouse CD45, and PE-Cy7 CD86 anti-mouse antibodies in the dark for 30 min. After centrifugation, washing with PBS, and resuspension in FWB, the same number of cells in each group was processed with a flow cytometer (CytoFLEX) and analyzed with FlowJo software (Version 10.4). Statistical analysis The experimental data were statistically analyzed using GraphPad Prism (version 9.0, San Diego, CA, USA). Data are presented as mean□±□SD from three independent replicates. Differences between the mean values of normally distributed data were assessed using one-way ANOVA (Dunnett’s test). P -value < 0.05, as indicated by “*”. P -value < 0.01 indicated that the difference was extremely significant, as indicated by “**.” Results ugpE deletion inhibited chain formation and capsular synthesis of SS2 To investigate the role of ugpE in SS2, an isogenic ugpE deletion mutant strain (Δ ugpE ) and a corresponding revertant strain (CΔ ugpE ) were constructed by homologous recombination (Fig. S1). We first examined the effect of ugpE on the growth kinetics. Although the Δ ugpE mutant appeared to grow more slowly than the SC19 wild-type, as observed by the growth curve, the differences between each group were not statistically significant ( Fig. 1A ). Interestingly, observation of cell morphology by Gram staining and light microscopy revealed that the Δ ugpE mutant displayed abnormal cell chain formation compared to the wild-type ( Fig. 1B and C ). After 72h of culture in THB medium, the majority of the bacterial chains of the SC19 wildtype consisted of 1–4 cell (s) per chain (approximately 80%), while the rest consisted of more than 5 cells per chain, and some even displayed very long chains with more than 10 cells, which was not observed in the Δ ugpE mutant ( Fig. 1C ; Fig. S2). On the other hand, most of the Δ ugpE mutants consisted of only 1–3 cell (s) (approximately 95%), and bacteria consisting of more than four cells only accounted for a minor proportion. The majority of the revertant strains also consisted of 1–4 cell (s) (approximately 70%), but no cells with long chains (>10 cells per chain) were found ( Fig. 1C ; Fig. S2). Moreover, deletion of ugpE also led to a significantly decreased cell width compared to the SC19 wildtype, as confirmed by transmission electron microscopy (TEM) ( Fig. 1D and E ). Overall, these results suggest a role for ugpE in regulating SS2 chain formation. Download figure Open in new tab Fig. 1. ugpE deletion inhibited chain formation and capsular synthesis of SS2. (A) Growth kinetics of SC19 wildtype, Δ UGPE and CΔ UGPE at 37°C. (B) Observation of cell morphology by Gram staining and light microscopy (1000×). (C) Analysis of cell number per chain in each group of cells. The quantification is based on results from at least three independent experiments with the assessment of 200 cells from each group. (D) Observation of cell morphology by transmission electron microscopy (TEM). Size bar, 1 μm. (E) Analysis of cell width in each group of cells. The quantification is based on results from at least three independent experiments with the assessment of 20 cells from each group. (F) Observation of capsule structure by TEM. Size bar, 200 nm. (G) Analysis of capsular thickness in each group of cells. The quantification is based on results from at least three independent experiments with the assessment of 20 cells from each group. (H) Analysis of mRNA levels of cps regulon genes cps-2B , cps-2C , cps-2S , and cps-2M by qRT-PCR. The data are presented as mean ± SD. Data were analyzed using one-way ANOVA (Dunnett’s test) (C, E, G) and paired t tests (H), respectively. *** P < 0.001; ** P < 0.01; * P < 0.05. ns, not significant. Of note, TEM also showed that the SC19 wild-type had a thick capsule structure, while the capsule structure of Δ ugpE was hardly observed ( Fig. 1F ). In line with this, the capsular thickness of the Δ ugpE strain was significantly thinner than that of the SC19 and revertant strains ( Fig. 1G ). In contrast, cell wall thickness showed no obvious differences among the groups ( Fig. 1H ). Knowing that the bacterial capsule structure was abolished, we assessed the level at which ugpE affected the capsular regulon genes. The cps gene cluster of SS2 comprises 25 genes [ 40 ], and we chose several of them for qRT-PCR analysis. Compared to the SC19 wildtype, the mRNA levels of cps-2B , cps-2C , and cps-2S were downregulated, while the mRNA levels of cps-2M and cps-2R were not affected ( Fig. 1I ). Overall, these results indicate that ugpE is required for capsule synthesis of SS2. ugpE deletion led to decreased tolerance to environmental stresses In a series of processes, such as survival and pathogenesis, pathogens have to face various stresses from constantly changing environments, such as acid-base tolerance and hydrogen peroxide. The anti-stress ability directly determines bacterial survival; thus, we determined the bacterial anti-stress ability by exposing it to various stress challenges, including heat stress, hydrogen peroxide killing, and acid-base tolerance. As shown in Fig. 2A , the number of recovered viable bacteria in the Δ ugpE mutant was significantly lower than in the SC19 wildtype at both 37°C and 40°C ( Fig. 2A ). Similarly, the Δ ugpE mutant was more sensitive to hydrogen peroxide (30 mM) than the SC19 wildtype and revertant strain ( Fig. 2B ), indicating that the antioxidant capacity of SS2 was downregulated after ugpE deletion. Moreover, the acid-base tolerance test showed that the survival ability of the Δ ugpE mutant was significantly lower than that of the SC19 wild-type and revertant strains at all indicated pH points, except at pH8, where no differences were observed between the groups ( Fig. 2C ). Overall, these results suggest that ugpE contributes to bacterial resistance to high-temperature adaptability, hydrogen peroxide, and acid-base tolerance. Download figure Open in new tab Fig. 2. ugpE deletion led to decreased tolerance to stresses. (A) Heat stress assay of SC19 wildtype, Δ ugpE and CΔ ugpE at 37°C and 40°C. (B) Oxidative stress assay of each group of cells. Cells were treated with hydrogen peroxide (30 mM). (C) Acid-base stress assay of each group of cells. The data are presented as mean ± SD. Data were analyzed using one-way ANOVA (Dunnett’s test). *** P < 0.001; ** P < 0.01; * P < 0.05. ns, not significant. ugpE deletion upregulated SS2 biofilm formation Biofilm formation represents a protective mode of growth that enables pathogens to survive in hostile environments [ 41 ]. Since deletion of ugpE led to decreased anti-stress ability, we wondered if biofilm formation by SC19 was also affected by ugpE. To this end, each group of strains was cultured on 96-well polystyrene plates for 24h, 48h, and 72h, and then stained with crystal violet to visualize biofilm formation. We observed that the biofilms were mainly formed as a ring at the air-liquid interface ( Fig. 3A ). Interestingly, the biofilms of the Δ ugpE mutant displayed a significantly higher level of adherence to the abiotic polystyrene wall of the well surface after 24h, 48h, and 72h of incubation in standing culture at 37°C compared to the SC19 wild-type and revertant strains ( Fig. 3A and B ). We also detected the effect of ugpE on rdar (red, d ry, a nd rough) macrocolony morphotypes using a Congo red agar plate assay. Download figure Open in new tab Fig. 3. ugpE deletion up-regulated SS2 biofilm formation. (A) Observation of biofilms at the air-liquid interface formation on the 96-well plate polystyrene surface after 24h, 48h and 72h of incubation at 37°C. Adherent cells were stained with 0.2% crystal violet. (B) Quantification of biofilms by dissolution in 30% acetic acid and measurement of absorbance at OD595. (C) Analysis of rdar macrocolony morphotype by Congo red agar plate assay after 48h and 72h of incubation at 28°C and 37°C. The surface morphology of the colonies was plotted and analyzed by ImageJ software (1.8.0). (D) Cell morphology analysis by scanning electron microscopy (SEM) of from plate-grown colonies. Size bar, 2 μm. The data are presented as mean ± SD. Data were analyzed using one-way ANOVA (Dunnett’s test). *** P < 0.001; ** P < 0.01; * P < 0.05. ns, not significant. Congo red binds to polysaccharides containing contiguous β-(1→4)-linked D -glucopyranosyl units and β-(1→3)- D -glucans and has been used to identify exopolysaccharides in biofilms [ 42 ]. We found that the SC19 wild-type showed a dry and rough morphotype on Congo red agar plates after 48 h and 72 h at 28°C, whereas it was a light red and smooth colony at 37°C ( Fig. 3C ), suggesting that SC19 produces more extracellular matrix at 28°C than at 37°C. Notably, a drier and rougher morphotype was observed in the Δ ugpE mutant compared to the SC19 wild-type and the revertant strain at both temperatures ( Fig. 3C ), suggesting ugpE plays a role in the production of the extracellular matrix of SS2. To our knowledge, this is the first description of regulation of the SS2 rdar morphotype at the gene level. In agreement with the colony morphotype, SEM observation of the agar-grown colonies demonstrated that the production of extracellular matrix was upregulated in the Δ ugpE mutant compared to the SC19 wild-type and revertant strains ( Fig. 3D ). ugpE regulates virulence in vitro As ugpE contributes to the capsule production of SS2 ( Fig. 1F-H ), we assumed that the virulence phenotypes of SS2 might also be affected. We first checked hemolysin activity and found that the hemolysin ability of the Δ ugpE mutant was significantly decreased compared to that of the SC19 wild-type and revertant strains ( Fig. 4A ). Download figure Open in new tab Fig. 4. In vitro virulence after ugpE deletion. (A) Analysis of the hemolysin activity of SC19 wildtype, Δ ugpE and CΔ ugpE in 5% sheep blood. (B-C) Analysis of adhesion (B) and invasion (C) abilities of each group of cells to hCMEC/D3. (D) Analysis of mRNA levels of adhesion related genes srtA , sao , fbpS , gapdh , eno , and Sadp by qRT-PCR. (E) Survival in whole human blood of each group of cells. Cells were incubated with germ-free human whole blood at 37°C for 2h. (F) Assessment of anti-phagocytosis ability of each group of cells in porcine alveolar macrophages (PAM). The data are presented as mean ± SD. Data were analyzed using one-way ANOVA (Dunnett’s test). *** P < 0.001; ** P < 0.01; * P < 0.05. ns, not significant. The ability of bacteria to adhere to and invade host cells is particularly important for bacterial pathogenesis. Subsequently, we investigated the adherence and invasion of each group of strains into human microvascular endothelial cells (hCMEC/D3). Compared to the SC19 wild-type and revertant strains, we found that the number of both adhered and invaded Δ ugpE mutant cells to hCMEC/D3 was significantly higher ( Fig. 4B and C ). With this finding, the transcription levels of adhesion-related genes, including srtA , sao , gapdh, and eno were also increased compared to the SC19 wild-type and revertant strains, while the levels of fbps and Sadp were decreased and remained unchanged, respectively ( Fig. 4D ). These results indicate that ugpE represses adhesion and invasion of host cells. Bacterial survival in host blood and anti-phagocytosis ability are critical for immune evasion and the establishment of infection. We further assessed these abilities using whole-blood survival and PAM-mediated phagocytosis analyses. Compared to the SC19 wildtype, of which approximately 36% have survived after whole blood killing, the viability of the Δ ugpE mutant and the revertant strain declined to 21% and 25%, respectively ( Fig. 4E ). In line with this result, we found that the phagocytosis rate of the Δ ugpE mutant by PAM cells was significantly higher than that of the SC19 wild-type and revertant strains ( Fig. 4F ), suggesting that the decreased survival ability of the Δ ugpE mutant in human blood was possibly due to an increased susceptibility to PAM phagocytosis. ugpE is required for SS2 full virulence in vivo To determine the effect of ugpE on the virulence of SS2, an SS2 infection model was constructed in BALB/c mice, and the survival of the mice was assessed. The results showed that all the mice died within 3 days of infection by the SC19 wildtype, while no mice or only half of the mice died of infection by the Δ ugpE mutant and the revertant strain CΔ ugpE , respectively ( Fig. 5A ), suggesting ugpE is required for SS2 virulence. Furthermore, mice were infected with lower doses of the strains, and the clinical symptoms, weight changes, pathological changes, and bacterial load in the blood and organs were collected and analyzed. Compared to the SC19 wild-type and CΔ ugpE infection groups, mice infected with the Δ ugpE mutant had significantly lower clinical scores after 12h of infection ( Fig. 5B ), indicating dramatically relieved virulence of SS2 upon ugpE deletion. In terms of body weight, the three groups of infected mice showed similar trends, but the weight loss in the Δ ugpE mutant infection group was significantly lower than that in the SC19 wild-type and revertant strains ( Fig. 5C ). Moreover, the bacterial load in the blood and organs including the brain, liver, kidney, and lung, except in the spleen, was significantly reduced after 24h of infection with the Δ ugpE mutant compared to the SC19 wild-type ( Fig. 5D ), indicating that the colonization ability of SC19 in mice was reduced after ugpE deletion, and it was easier to be cleared by the host immune system. Download figure Open in new tab Fig. 5. Determination of bacterial virulence after ugpE deletion in mice. (A-C) Survival curves (A), clinical scores (B), and body weight changes (C) of the mice infected with SC19 wildtype, Δ ugpE and CΔ ugpE . (D) Bacterial counts in the major organs and blood of mice after infection with each group of cells. The data are presented as mean ± SD. Data were analyzed using paired t tests. *** P < 0.001; ** P < 0.01; * P < 0.05. ns, not significant. In line with these observations, the histopathological analysis of each organ revealed that the Δ ugpE mutant infected mice showed weaker pathological changes compared to mice infected with wild-type SC19 and CΔ ugpE ( Fig. 6 ). Specifically, infection with SC19 wild-type and CΔ ugpE led to infiltration of inflammatory cells, including monocytes and neutrophils, in all tissues, especially in the lungs, kidneys, brain, and spleen. Moreover, edema and hyperemia were observed in these tissues upon SC19 wild-type and CΔ ugpE infection. In contrast, infection with the Δ ugpE mutant alleviated the degree of infiltration of inflammatory cells, edema, and hyperemia, especially in the lungs and brain ( Fig. 6 ), indicating that deletion of ugpE impaired the virulence of SC19. Taken together, these results demonstrated ugpE is required for the full virulence of SS2 in mice. Download figure Open in new tab Fig. 6. Pathological changes in lung, liver, kidney, heart, brain, and spleen upon infection with SC19 wildtype, Δ ugpE and CΔ ugpE strains using histopathological analysis. The tissue slices were stained with hematoxylin and eosin (HE) and the histopathological changes were indicated with black arrows. ugpE deletion alters distribution of macrophages in major organs of mice upon infection Since ugpE is required for full virulence both in vitro and in vivo , we wondered whether the host immune response was also altered upon SS2 infection. To this end, the distribution of macrophages in the major organs of mice upon SS2 infection was assessed using flow cytometry. The results showed that the percentage of macrophages in the lung after 24h infection with the Δ ugpE mutant was significantly lower than that after infection with the SC19 wildtype and CΔ ugpE ( Fig. 7A and B ). However, the percentage of macrophages in other organs after 24h infection of with the Δ ugpE mutant was not significantly different from the other two groups ( Fig. 7A, C -F). Download figure Open in new tab Fig. 7. Distribution of macrophages in major organs of mice upon infection with SC19 wildtype, Δ ugpE and CΔ ugpE strains by flow cytometry. The data are presented as mean ± SD. Data were analyzed using one-way ANOVA (Dunnett’s test). *** P < 0.001; ** P < 0.01; * P < 0.05. ns, not significant. Discussion UgpABCE is a member of the ABC transporter superfamily that is involved in glycerophospholipid synthesis in E. coli [ 23 ]. In this study, we report a novel role of the Ugp transporter subunit UgpE in the regulation of various cellular phenotypes, including stress tolerance, biofilm formation, and virulence of the zoonotic pathogen S. suis . Deletion of ugpE impaired cell chain formation, capsular synthesis, and stress tolerance while upregulating biofilm formation and adhesion to hCMEC/D3 cells. Importantly, bacterial virulence was attenuated in mice after deletion of ugpE . These results suggest ugpE is a novel virulence factor that regulates the various cellular phenotypes of S. suis . UgpE is a subunit of the UgpABCE transporter system. This system is predicted to be prevalent in diverse bacteria [ 43 ] but has been well studied in E. coli and several other bacterial species only, including Mycobacterium tuberculosis [ 44 ] and Thermus thermophilus [ 45 ]. To the best of our knowledge, this is the first study to identify an UgpE homolog in S. suis . In E. coli , UgpE contributes to the transport of both G3P and glycerophosphodiesters from the periplasm to cytosol under phosphate starvation conditions [ 23 , 44 ]. Glycerophosphodiesters are degraded into G3P and further acylated by sn -glycerol-3-phosphate acyltransferase to initiate the biosynthesis of membrane glycerophospholipids or central carbon metabolism [ 46 , 47 ]. Indeed, glycerophosphodiesters are also taken up by Glp ( gl ycerol-3- p hosphate transporter), apart from the UgpABCE transporter system [ 48 ]. However, preliminary analysis demonstrated that no Glp homolo was present in the SC19 genome (data not shown), indicating that the UgpABCE transporter might be the sole system for G3P and glycerophosphodiester acquisition in SC19. Interestingly, we did not observe any obvious morphological changes in the cell membranes or cell walls among the groups ( Fig. 1F and H ). Considering the importance of glycerol phosphate in membrane phospholipid synthesis, we hypothesized that other cell wall components might be impaired by ugpE deletion. In addition to participating in glycerophospholipid biosynthesis, glycerophosphodiesters also serve as osmoprotectants in eukaryotic cells. In Saccharomyces cerevisiae , glycerophosphocholine produced from the membrane lipid phosphatidylcholine protects cells from hypersaline stress [ 25 ]. In line with this phenomenon, the Δ ugpE mutant dramatically diminished the anti-stress abilities of SC19 compared to the wild-type SC19 ( Fig. 2 ), suggesting ugpE is required for bacterial stress responses to adverse environmental conditions. Although the cell membrane and cell wall were hardly affected, the capsule structure almost disappeared ( Fig. 1F-G ). The capsule is a protective polysaccharide layer around the cell, which is an important virulence factor for most encapsulated streptococci. The absence of CPS correlates with increased phagocytosis by macrophages and decreased virulence in murine and pig models of infection [ 49 ]. In SS2, the capsular locus ( cps ) responsible for CPS biosynthesis involves 25 genes [ 40 ]. It has been shown that inactivation of the cps2B gene for polysaccharide chain length determination, cps2EF , cps2G , cps2J and cps2L genes for glycosyltransferases leads to impaired capsule production [ 7 , 50 ]. cpsBCD genes form a tyrosine phosphoregulatory system that controls the CPS assembly machinery, of which CpsB assists in CpsD dephosphorylation and its interaction with CpsC, leading to elevated CPS polymerization [ 51 , 52 ]. The cpsPQRST genes showed homology to the NeuBCDA proteins of Group B Streptococcus (GBS) and E. coli and thus have been predicted to be involved in the synthesis of sialic acid (NeuNAc), one of the main components of the CPS of S. suis [ 40 ]. Inactivation of neuC ( cpsQR ) resulted in the loss of the whole capsule of S. suis , decreased the anti-phagocytosis ability of macrophages, and impaired virulence in mice [ 53 ]. In GBS, neuD functions as a Sia O-acetyltransferase and is required for the synthesis of the unique sialylated CPS shared only by S. suis and GBS [ 54 , 55 ]. In this study, a reduction in the transcription levels of cps-2B , cps-2C and cps-2S was observed in the Δ ugpE mutant ( Fig. 1I ), suggesting that the unencapsulated phenotype of the Δ ugpE mutant may be due to interference with polysaccharide chain formation and the expression of sialic acid for CPS synthesis in S. suis . In line with these observations, the unencapsulated Δ ugpE mutant exhibited a lower survival rate in whole human blood, antiphagocytic ability against PAM, and decreased virulence in mice compared to the SC19 wild-type ( Fig. 4E-F ; Fig. 5 ), suggesting that deficiency in CPS development is a critical reason for the weakened virulence of S. suis by ugpE deletion. Moreover, only three primary capsule synthesis pathways have been identified so far. The Wzx/Wzy-dependent and synthase-dependent pathways are present in both gram-positive and gram-negative bacteria, while the ABC transporter-dependent pathway is present only in gram-negative bacteria [ 56 , 57 ]. Capsule synthesis is regulated by small RNAs (sRNA). In S. suis , sRNA rss04 contributes to meningitis induction in mice by regulating CPS synthesis [ 58 ]. In this study, we identified for the first time that UgpE, which belongs to the Ugp transporter system, regulates CPS synthesis in Gram positive streptococci. Notably, both the adhesion and invasion abilities of host hCMEC/D3 cells were enhanced in the Δ ugpE mutant compared to those in the SC19 wild-type ( Fig. 4B-C ). We speculated that although CPS is a critical antiphagocytic factor that resists phagocytosis by macrophages and neutrophils in the blood, it may interfere with the adhesion and invasion of host cells by hindering cell wall components, especially some vital virulence factors located on the cell surface for adhesion. Indeed, many studies have demonstrated that the repression of CPS production enhances the adhesion and invasion of SS2 to host cells and impairs virulence in mice [ 58 , 59 , 60 ]. As anticipated, the transcription levels of genes encoding cell surface virulence factors, including srtA , sao , gapdh, and eno were upregulated in the Δ ugpE mutant compared to those in the parental strain ( Fig. 4D ). These results suggest that impairment of CPS by the Δ ugpE mutant may lead to exposure of cell surface proteins, which contributes to bacterial adhesion and invasion of host cells. In contrast, impairment in CPS decreased antiphagocytic ability against macrophages and neutrophils in the blood, resulting in attenuated virulence, as confirmed by the mouse infection model ( Fig. 5 ; Fig. 6 ). Biofilm formation represents a protected mode of growth that renders bacterial cells less susceptible to host immune responses and thus enables pathogens to survive in hostile environments [ 41 ]. Interestingly, the Δ ugpE mutant exhibited enhanced biofilm formation on the polystyrene surface, along with decreased survival in whole human blood and anti-phagocytic ability in PAM ( Fig. 3A-B ; Fig. E-F). Considering the critical role of CPS in the resistance to phagocytosis, we reasoned that infection by the Δ ugpE mutant may not be established due to the loss of CPS structure, even through the upregulation of biofilm formation. Indeed, studies have shown that the CPS structure affects bacterial biofilm formation. In S. pneumoniae , encapsulated clinical pneumococcal isolates are impaired in their capacity to form biofilms, and reduction in the amount of CPS is usually correlated with increased biofilm-forming capacity [ 61 ]. In SS2, the flavonoid compound rutin specifically downregulated biofilm formation by interfering with CPS biosynthesis [ 62 ]. In summary, our study reported for the first time that UgpE, which belongs to the Ugp transporter system, is required for full virulence and biofilm formation of the zoonotic pathogen S. suis . UgpE contributes to bacterial virulence by positively regulating CPS synthesis, demonstrating that UgpE is a novel virulence factor of S. suis . Our results expand the current knowledge on the pathogenesis of S. suis . Disclosure statement No potential conflict of interest was reported by the author(s). Ethical statement Animal infection experiments were conducted at the Laboratory Animal Center of College of Veterinary Medicine, Jilin University (Permit number: KT202103086) in accordance with the Regulations for the Administration of affairs Concerning Experimental Animals. Funding This work was supported by the National Key Research and Development Project Program of China (No. 2022YFD1800905), National Natural Science Foundation of China (No. 32102670), and the Natural Science Foundation of Jilin Province (No. 20220101295JC). Authors’ contributions Qiulei Yang : Methodology, Data curation, formal analysis, Investigation, Writing–original draft. Na Li : Methodology, Data curation, formal analysis, and investigation. Yanyan Tian : Methodology, Investigation. Qiao Liang, Miaomiao Zhao, Hong Chu : Validation, Visualization. Yan Gong, Tong Wu, Shaopeng Wei, He Wang : Investigation. Guangmou Yan : Resources. Fengyang Li : Conceptualization, Funding acquisition, Supervision, Writing–original draft, writing–review, and editing. Liancheng Lei : Funding acquisition, Supervision, Project administration, Resources, Writing, review, and editing. Data availability statement All data generated or analyzed during this study are deposited in Figshare (10.6084/m9.figshare.27094336). Acknowledgements We thank Prof. Anding Zhang (Huazhong Agricultural University, Wuhan, China) for providing S. suis serotype 2 (SS2) strain SC19, and Prof. Yan Chen (Jilin University, Changchun, China) for providing hCMEC/D3 cell line. Footnotes https://doi.org/10.6084/m9.figshare.27094336.v1 References 1. ↵ Feng Y , Zhang H , Ma Y , et al. Uncovering newly emerging variants of Streptococcus suis, an important zoonotic agent . Trends in microbiology . 2010 Mar ; 18 ( 3 ): 124 – 31 . doi: 10.1016/j.tim.2009.12.003 . PubMed PMID: 20071175 ; eng. OpenUrl CrossRef PubMed 2. ↵ Goyette-Desjardins G , Auger JP , Xu J , et al. Streptococcus suis, an important pig pathogen and emerging zoonotic agent-an update on the worldwide distribution based on serotyping and sequence typing . Emerging microbes & infections . 2014 Jun ; 3 ( 6 ): e45 . doi: 10.1038/emi.2014.45 . PubMed PMID: 26038745 ; PubMed Central PMCID: PMCPMC4078792 . eng. OpenUrl CrossRef PubMed 3. ↵ Yu H , Jing H , Chen Z , et al. Human Streptococcus suis outbreak, Sichuan, China . Emerging infectious diseases . 2006 Jun ; 12 ( 6 ): 914 – 20 . doi: 10.3201/eid1206.051194 . PubMed PMID: 16707046 ; PubMed Central PMCID: PMCPMC3373052 . eng. OpenUrl CrossRef PubMed Web of Science 4. ↵ Mai NT , Hoa NT , Nga TV , et al. Streptococcus suis meningitis in adults in Vietnam . Clinical infectious diseases: an official publication of the Infectious Diseases Society of America . 2008 Mar 1 ; 46 ( 5 ): 659 – 67 . doi: 10.1086/527385 . PubMed PMID: 19413493 ; eng. OpenUrl CrossRef PubMed Web of Science 5. ↵ Ma E , Chung PH , So T , et al. Streptococcus suis infection in Hong Kong: an emerging infectious disease? Epidemiology and infection . 2008 Dec ; 136 ( 12 ): 1691 – 7 . doi: 10.1017/s0950268808000332 . PubMed PMID: 18252026 ; PubMed Central PMCID: PMCPMC2870785 . eng. OpenUrl CrossRef PubMed 6. ↵ Rayanakorn A , Katip W , Goh BH , et al. Clinical Manifestations and Risk Factors of Streptococcus suis Mortality Among Northern Thai Population: Retrospective 13-Year Cohort Study . Infection and drug resistance . 2019 ; 12 : 3955 – 3965 . doi: 10.2147/idr.S233326 . PubMed PMID: 32021313 ; PubMed Central PMCID: PMCPMC6941973 . eng. OpenUrl CrossRef PubMed 7. ↵ Smith HE , Damman M , van der Velde J , et al. Identification and characterization of the cps locus of Streptococcus suis serotype 2: the capsule protects against phagocytosis and is an important virulence factor . Infection and immunity . 1999 Apr ; 67 ( 4 ): 1750 – 6 . doi: 10.1128/iai.67.4.1750-1756.1999 . PubMed PMID: 10085014 ; PubMed Central PMCID: PMCPMC96524 . eng. OpenUrl Abstract / FREE Full Text 8. ↵ Smith HE , Reek FH , Vecht U , et al. Repeats in an extracellular protein of weakly pathogenic strains of Streptococcus suis type 2 are absent in pathogenic strains . Infection and immunity . 1993 Aug ; 61 ( 8 ): 3318 – 26 . doi: 10.1128/iai.61.8.3318-3326.1993 . PubMed PMID: 8335363 ; PubMed Central PMCID: PMCPMC281006 . eng. OpenUrl Abstract / FREE Full Text 9. ↵ Vecht U , Wisselink HJ , Jellema ML , et al. Identification of two proteins associated with virulence of Streptococcus suis type 2 . Infection and immunity . 1991 Sep ; 59 ( 9 ): 3156 – 62 . doi: 10.1128/iai.59.9.3156-3162.1991 . PubMed PMID: 1879937 ; PubMed Central PMCID: PMCPMC258147 . eng. OpenUrl Abstract / FREE Full Text 10. ↵ Jacobs AA , Loeffen PL , van den Berg AJ, et al. Identification, purification, and characterization of a thiol-activated hemolysin (suilysin) of Streptococcus suis . Infection and immunity . 1994 May ; 62 ( 5 ): 1742 – 8 . doi: 10.1128/iai.62.5.1742-1748.1994 . PubMed PMID: 8168935 ; PubMed Central PMCID: PMCPMC186398 . eng. OpenUrl Abstract / FREE Full Text 11. ↵ Okwumabua O , Persaud JS , Reddy PG . Cloning and characterization of the gene encoding the glutamate dehydrogenase of Streptococcus suis serotype 2 . Clinical and diagnostic laboratory immunology . 2001 Mar ; 8 ( 2 ): 251 – 7 . doi: 10.1128/cdli.8.2.251-257.2001 . PubMed PMID: 11238204 ; PubMed Central PMCID: PMCPMC96045 . eng. OpenUrl Abstract / FREE Full Text 12. ↵ de Greeff A , Buys H , Verhaar R , et al. Contribution of fibronectin-binding protein to pathogenesis of Streptococcus suis serotype 2 . Infection and immunity . 2002 Mar ; 70 ( 3 ): 1319 – 25 . doi: 10.1128/iai.70.3.1319-1325.2002 . PubMed PMID: 11854216 ; PubMed Central PMCID: PMCPMC127759 . eng. OpenUrl Abstract / FREE Full Text 13. ↵ Li W , Wan Y , Tao Z , et al. A novel fibronectin-binding protein of Streptococcus suis serotype 2 contributes to epithelial cell invasion and in vivo dissemination . Veterinary microbiology . 2013 Feb 22 ; 162 ( 1 ): 186 – 94 . doi: 10.1016/j.vetmic.2012.09.004 . PubMed PMID: 23021642 ; eng. OpenUrl CrossRef PubMed 14. ↵ Rees DC , Johnson E , Lewinson O . ABC transporters: the power to change . Nature reviews Molecular cell biology . 2009 Mar ; 10 ( 3 ): 218 – 27 . doi: 10.1038/nrm2646 . PubMed PMID: 19234479 ; PubMed Central PMCID: PMCPMC2830722 . eng. OpenUrl CrossRef PubMed Web of Science 15. ↵ Shea AE , Forsyth VS , Stocki JA , et al. Emerging roles for ABC transporters as virulence factors in uropathogenic Escherichia coli . Proceedings of the National Academy of Sciences of the United States of America . 2024 Apr 16 ; 121 ( 16 ): e2310693121 . doi: 10.1073/pnas.2310693121 . PubMed PMID: 38607934 ; PubMed Central PMCID: PMCPMC11032443 . eng. OpenUrl CrossRef PubMed 16. ↵ Domenech P , Kobayashi H , LeVier K , et al. BacA, an ABC transporter involved in maintenance of chronic murine infections with Mycobacterium tuberculosis . Journal of bacteriology . 2009 Jan ; 191 ( 2 ): 477 – 85 . doi: 10.1128/jb.01132-08 . PubMed PMID: 18996991 ; PubMed Central PMCID: PMCPMC2620812 . eng. OpenUrl Abstract / FREE Full Text 17. ↵ Shen X , Zhong Q , Zhao Y , et al. Proteome analysis of the two-component SalK/SalR system in Epidemic Streptococcus suis serotype 2 . Current microbiology . 2013 Jul ; 67 ( 1 ): 118 – 22 . doi: 10.1007/s00284-013-0343-4 . PubMed PMID: 23463517 ; eng. OpenUrl CrossRef PubMed 18. ↵ Zhang W , Liu G , Tang F , et al. Pre-absorbed immunoproteomics: a novel method for the detection of Streptococcus suis surface proteins . PloS one . 2011 ; 6 ( 6 ): e21234 . doi: 10.1371/journal.pone.0021234 . PubMed PMID: 21713002 ; PubMed Central PMCID: PMCPMC3119691 . eng. OpenUrl CrossRef PubMed 19. ↵ Pian Y , Wang P , Liu P , et al. Proteomics identification of novel fibrinogen-binding proteins of Streptococcus suis contributing to antiphagocytosis . Frontiers in cellular and infection microbiology . 2015 ; 5 : 19 . doi: 10.3389/fcimb.2015.00019 . PubMed PMID: 25789245 ; PubMed Central PMCID: PMCPMC4349166 . eng. OpenUrl CrossRef PubMed 20. ↵ Li Q , Liu H , Du D , et al. Identification of Novel Laminin- and Fibronectin-binding Proteins by Far-Western Blot: Capturing the Adhesins of Streptococcus suis Type 2 . Frontiers in cellular and infection microbiology . 2015 ; 5 : 82 . doi: 10.3389/fcimb.2015.00082 . PubMed PMID: 26636044 ; PubMed Central PMCID: PMCPMC4644805 . eng. OpenUrl CrossRef PubMed 21. ↵ Tan MF , Gao T , Liu WQ , et al. MsmK, an ATPase, Contributes to Utilization of Multiple Carbohydrates and Host Colonization of Streptococcus suis . PloS one . 2015 ; 10 ( 7 ): e0130792 . doi: 10.1371/journal.pone.0130792 . PubMed PMID: 26222651 ; PubMed Central PMCID: PMCPMC4519317 . eng. OpenUrl CrossRef PubMed 22. ↵ Zhao YL , Zhou YH , Chen JQ , et al. Quantitative proteomic analysis of sub-MIC erythromycin inhibiting biofilm formation of S. suis in vitro . Journal of proteomics . 2015 Feb 26 ; 116 : 1 – 14 . doi: 10.1016/j.jprot.2014.12.019 . PubMed PMID: 25579403 ; eng. OpenUrl CrossRef PubMed 23. ↵ Wuttge S , Bommer M , Jäger F , et al. Determinants of substrate specificity and biochemical properties of the sn-glycerol-3-phosphate ATP binding cassette transporter (UgpB-AEC2) of Escherichia coli . Molecular microbiology . 2012 Nov ; 86 ( 4 ): 908 – 20 . doi: 10.1111/mmi.12025 . PubMed PMID: 23013274 ; eng. OpenUrl CrossRef PubMed 24. ↵ Boos W . Binding protein-dependent ABC transport system for glycerol 3-phosphate of Escherichia coli . Methods in enzymology . 1998 ; 292 : 40 – 51 . doi: 10.1016/s0076-6879(98)92006-7 . PubMed PMID: 9711545 ; eng. OpenUrl CrossRef PubMed 25. ↵ Kiewietdejonge A , Pitts M , Cabuhat L , et al. Hypersaline stress induces the turnover of phosphatidylcholine and results in the synthesis of the renal osmoprotectant glycerophosphocholine in Saccharomyces cerevisiae . FEMS yeast research . 2006 Mar ; 6 ( 2 ): 205 – 17 . doi: 10.1111/j.1567-1364.2006.00030.x . PubMed PMID: 16487344 ; eng. OpenUrl CrossRef PubMed 26. ↵ Ohshima N , Yamashita S , Takahashi N , et al. Escherichia coli cytosolic glycerophosphodiester phosphodiesterase (UgpQ) requires Mg2+, Co2+, or Mn2+ for its enzyme activity . Journal of bacteriology . 2008 Feb ; 190 ( 4 ): 1219 – 23 . doi: 10.1128/jb.01223-07 . PubMed PMID: 18083802 ; PubMed Central PMCID: PMCPMC2238210 . eng. OpenUrl Abstract / FREE Full Text 27. ↵ Fischer KE , Bremer E . Activity of the osmotically regulated yqiHIK promoter from Bacillus subtilis is controlled at a distance . Journal of bacteriology . 2012 Oct ; 194 ( 19 ): 5197 – 208 . doi: 10.1128/jb.01041-12 . PubMed PMID: 22843846 ; PubMed Central PMCID: PMCPMC3457214 . eng. OpenUrl Abstract / FREE Full Text 28. ↵ Großhennig S , Schmidl SR , Schmeisky G , et al. Implication of glycerol and phospholipid transporters in Mycoplasma pneumoniae growth and virulence . Infection and immunity . 2013 Mar ; 81 ( 3 ): 896 – 904 . doi: 10.1128/iai.01212-12 . PubMed PMID: 23297388 ; PubMed Central PMCID: PMCPMC3584876 . eng. OpenUrl Abstract / FREE Full Text 29. ↵ Schmidl SR , Otto A , Lluch-Senar M , et al. A trigger enzyme in Mycoplasma pneumoniae: impact of the glycerophosphodiesterase GlpQ on virulence and gene expression . PLoS pathogens . 2011 Sep ; 7 ( 9 ): e1002263 . doi: 10.1371/journal.ppat.1002263 . PubMed PMID: 21966272 ; PubMed Central PMCID: PMCPMC3178575 . eng. OpenUrl CrossRef PubMed 30. ↵ Takamatsu D , Osaki M , Sekizaki T . Thermosensitive suicide vectors for gene replacement in Streptococcus suis . Plasmid . 2001 Sep ; 46 ( 2 ): 140 – 8 . doi: 10.1006/plas.2001.1532 . PubMed PMID: 11591139 ; eng. OpenUrl CrossRef PubMed Web of Science 31. ↵ Takamatsu D , Osaki M , Sekizaki T . Construction and characterization of Streptococcus suis-Escherichia coli shuttle cloning vectors . Plasmid . 2001 Mar ; 45 ( 2 ): 101 – 13 . doi: 10.1006/plas.2000.1510 . PubMed PMID: 11322824 ; eng. OpenUrl CrossRef PubMed Web of Science 32. ↵ Wang Y , Wang Y , Liu B , et al. pdh modulate virulence through reducing stress tolerance and biofilm formation of Streptococcus suis serotype 2 . Virulence . 2019 Dec ; 10 ( 1 ): 588 – 599 . doi: 10.1080/21505594.2019.1631661 . PubMed PMID: 31232165 ; PubMed Central PMCID: PMCPMC6592368 . eng. OpenUrl CrossRef PubMed 33. ↵ Vanier G , Segura M , Friedl P , et al. Invasion of porcine brain microvascular endothelial cells by Streptococcus suis serotype 2 . Infection and immunity . 2004 Mar ; 72 ( 3 ): 1441 – 9 . doi: 10.1128/iai.72.3.1441-1449.2004 . PubMed PMID: 14977949 ; PubMed Central PMCID: PMCPMC356020 . eng. OpenUrl Abstract / FREE Full Text 34. ↵ Zhu J , Zhu R , Jiang H , et al. Adh Promotes Actinobacillus pleuropneumoniae Survival in Porcine Alveolar Macrophages by Inhibiting CHAC2-Mediated Respiratory Burst and Inflammatory Cytokine Expression . Cells . 2023 Feb 22 ; 12 ( 5 ). doi: 10.3390/cells12050696 . PubMed PMID: 36899832 ; PubMed Central PMCID: PMCPMC10001268 . eng. OpenUrl CrossRef PubMed 35. ↵ Li F , Cimdins A , Rohde M , et al. DncV Synthesizes Cyclic GMP-AMP and Regulates Biofilm Formation and Motility in Escherichia coli ECOR31 . mBio . 2019 Mar 5 ; 10 ( 2 ). doi: 10.1128/mBio.02492-18 . PubMed PMID: 30837338 ; PubMed Central PMCID: PMCPMC6401482 . eng. OpenUrl Abstract / FREE Full Text 36. ↵ Li F , Cao L , Bähre H , et al. Patatin-like phospholipase CapV in Escherichia coli - morphological and physiological effects of one amino acid substitution . NPJ biofilms and microbiomes . 2022 May 11 ; 8 ( 1 ): 39 . doi: 10.1038/s41522-022-00294-z . PubMed PMID: 35546554 ; PubMed Central PMCID: PMCPMC9095652 . eng. OpenUrl CrossRef PubMed 37. ↵ Li F , Liang D , Yang Z , et al. Astragalin suppresses inflammatory responses via down-regulation of NF-κB signaling pathway in lipopolysaccharide-induced mastitis in a murine model . International immunopharmacology . 2013 Oct ; 17 ( 2 ): 478 – 82 . doi: 10.1016/j.intimp.2013.07.010 . PubMed PMID: 23928506 ; eng. OpenUrl CrossRef PubMed 38. ↵ Gerber J , Raivich G , Wellmer A , et al. A mouse model of Streptococcus pneumoniae meningitis mimicking several features of human disease . Acta neuropathologica . 2001 May ; 101 ( 5 ): 499 – 508 . doi: 10.1007/s004010000326 . PubMed PMID: 11484822 ; eng. OpenUrl CrossRef PubMed 39. ↵ Jiang X , Li F , Mei J , et al. Brain Immune Cell Infiltration and Serum Metabolomic Characteristics Reveal that Lauric Acid Promotes Immune Cell Infiltration in Brain and Streptococcus suis Meningitis in Mice . Molecular neurobiology . 2024 Apr 16 . doi: 10.1007/s12035-024-04144-1 . PubMed PMID: 38625620 ; eng. OpenUrl CrossRef PubMed 40. ↵ Smith HE , de Vries R , van’t Slot R , et al. The cps locus of Streptococcus suis serotype 2: genetic determinant for the synthesis of sialic acid . Microbial pathogenesis . 2000 Aug ; 29 ( 2 ): 127 – 34 . doi: 10.1006/mpat.2000.0372 . PubMed PMID: 10906268 ; eng. OpenUrl CrossRef PubMed 41. ↵ Del Pozo JL . Biofilm-related disease . Expert review of anti-infective therapy . 2018 Jan ; 16 ( 1 ): 51 – 65 . doi: 10.1080/14787210.2018.1417036 . PubMed PMID: 29235402 ; eng. OpenUrl CrossRef PubMed 42. ↵ Grenier D , Grignon L , Gottschalk M . Characterisation of biofilm formation by a Streptococcus suis meningitis isolate . Veterinary journal (London, England: 1997) . 2009 Feb ; 179 ( 2 ): 292 – 5 . doi: 10.1016/j.tvjl.2007.09.005 . PubMed PMID: 17964204 ; eng. OpenUrl CrossRef PubMed Web of Science 43. ↵ Luo H , Benner R , Long RA , et al. Subcellular localization of marine bacterial alkaline phosphatases . Proceedings of the National Academy of Sciences of the United States of America . 2009 Dec 15 ; 106 ( 50 ): 21219 – 23 . doi: 10.1073/pnas.0907586106 . PubMed PMID: 19926862 ; PubMed Central PMCID: PMCPMC2795515 . eng. OpenUrl Abstract / FREE Full Text 44. ↵ Jiang D , Zhang Q , Zheng Q , et al. Structural analysis of Mycobacterium tuberculosis ATP-binding cassette transporter subunit UgpB reveals specificity for glycerophosphocholine . The FEBS journal . 2014 Jan ; 281 ( 1 ): 331 – 41 . doi: 10.1111/febs.12600 . PubMed PMID: 24299297 ; eng. OpenUrl CrossRef PubMed 45. ↵ Chandravanshi M , Gogoi P , Kanaujia SP . Computational characterization of TTHA0379: A potential glycerophosphocholine binding protein of Ugp ATP-binding cassette transporter . Gene . 2016 Nov 5 ; 592 ( 2 ): 260 – 8 . doi: 10.1016/j.gene.2016.07.017 . PubMed PMID: 27395429 ; eng. OpenUrl CrossRef PubMed 46. ↵ Cronan JE . Bacterial membrane lipids: where do we stand? Annual review of microbiology . 2003 ; 57 : 203 – 24 . doi: 10.1146/annurev.micro.57.030502.090851 . PubMed PMID: 14527277 ; eng. OpenUrl CrossRef PubMed Web of Science 47. ↵ Liu Y , Sun W , Ma L , et al. Metabolic Mechanism and Physiological Role of Glycerol 3-Phosphate in Pseudomonas aeruginosa PAO1 . mBio . 2022 Dec 20 ; 13 ( 6 ): e0262422 . doi: 10.1128/mbio.02624-22 . PubMed PMID: 36218368 ; PubMed Central PMCID: PMCPMC9765544 . eng. OpenUrl CrossRef PubMed 48. ↵ Tommassen J , Eiglmeier K , Cole ST , et al. Characterization of two genes, glpQ and ugpQ, encoding glycerophosphoryl diester phosphodiesterases of Escherichia coli . Molecular & general genetics: MGG . 1991 Apr ; 226 ( 1-2 ): 321 – 7 . doi: 10.1007/bf00273621 . PubMed PMID: 1851953 ; eng. OpenUrl CrossRef PubMed 49. ↵ Charland N , Harel J , Kobisch M , et al. Streptococcus suis serotype 2 mutants deficient in capsular expression . Microbiology (Reading, England) . 1998 Feb ; 144 ( Pt 2 ): 325 – 332 . doi: 10.1099/00221287-144-2-325 . PubMed PMID: 9493370 ; eng. OpenUrl CrossRef PubMed Web of Science 50. ↵ Zhang Y , Ding D , Liu M , et al. Effect of the glycosyltransferases on the capsular polysaccharide synthesis of Streptococcus suis serotype 2 . Microbiological research . 2016 Apr ; 185 : 45 – 54 . doi: 10.1016/j.micres.2016.02.002 . PubMed PMID: 26946377 ; eng. OpenUrl CrossRef PubMed 51. ↵ Morona JK , Paton JC , Miller DC , et al. Tyrosine phosphorylation of CpsD negatively regulates capsular polysaccharide biosynthesis in streptococcus pneumoniae . Molecular microbiology . 2000 Mar ; 35 ( 6 ): 1431 – 42 . doi: 10.1046/j.1365-2958.2000.01808.x . PubMed PMID: 10760144 ; eng. OpenUrl CrossRef PubMed Web of Science 52. ↵ Nourikyan J , Kjos M , Mercy C , et al. Autophosphorylation of the Bacterial Tyrosine-Kinase CpsD Connects Capsule Synthesis with the Cell Cycle in Streptococcus pneumoniae . PLoS genetics . 2015 Sep ; 11 ( 9 ): e1005518 . doi: 10.1371/journal.pgen.1005518 . PubMed PMID: 26378458 ; PubMed Central PMCID: PMCPMC4574921 . eng. OpenUrl CrossRef PubMed 53. ↵ Lecours MP , Fittipaldi N , Takamatsu D , et al. Sialylation of Streptococcus suis serotype 2 is essential for capsule expression but is not responsible for the main capsular epitope . Microbes and infection . 2012 Sep ; 14 ( 11 ): 941 – 50 . doi: 10.1016/j.micinf.2012.03.008 . PubMed PMID: 22521569 ; eng. OpenUrl CrossRef PubMed 54. ↵ Lewis AL , Hensler ME , Varki A , et al. The group B streptococcal sialic acid O-acetyltransferase is encoded by neuD, a conserved component of bacterial sialic acid biosynthetic gene clusters . The Journal of biological chemistry . 2006 Apr 21 ; 281 ( 16 ): 11186 – 92 . doi: 10.1074/jbc.M513772200 . PubMed PMID: 16490781 ; eng. OpenUrl Abstract / FREE Full Text 55. ↵ Roy D , Takamatsu D , Okura M , et al. Capsular Sialyltransferase Specificity Mediates Different Phenotypes in Streptococcus suis and Group B Streptococcus . Frontiers in microbiology . 2018 ; 9 : 545 . doi: 10.3389/fmicb.2018.00545 . PubMed PMID: 29666608 ; PubMed Central PMCID: PMCPMC5891629 . eng. OpenUrl CrossRef PubMed 56. ↵ Gao S , Jin W , Quan Y , et al. Bacterial capsules: Occurrence, mechanism, and function . NPJ biofilms and microbiomes . 2024 Mar 13 ; 10 ( 1 ): 21 . doi: 10.1038/s41522-024-00497-6 . PubMed PMID: 38480745 ; PubMed Central PMCID: PMCPMC10937973 . eng. OpenUrl CrossRef PubMed 57. ↵ Whitfield C , Wear SS , Sande C . Assembly of Bacterial Capsular Polysaccharides and Exopolysaccharides . Annual review of microbiology . 2020 Sep 8 ; 74 : 521 – 543 . doi: 10.1146/annurev-micro-011420-075607 . PubMed PMID: 32680453 ; eng. OpenUrl CrossRef PubMed 58. ↵ Xiao G , Tang H , Zhang S , et al. Streptococcus suis small RNA rss04 contributes to the induction of meningitis by regulating capsule synthesis and by inducing biofilm formation in a mouse infection model . Veterinary microbiology . 2017 Feb ; 199 : 111 – 119 . doi: 10.1016/j.vetmic.2016.12.034 . PubMed PMID: 28110777 ; eng. OpenUrl CrossRef PubMed 59. ↵ Feng Y , Cao M , Shi J , et al. Attenuation of Streptococcus suis virulence by the alteration of bacterial surface architecture . Scientific reports . 2012 ; 2 : 710 . doi: 10.1038/srep00710 . PubMed PMID: 23050094 ; PubMed Central PMCID: PMCPMC3464449 . eng. OpenUrl CrossRef PubMed 60. ↵ Segura MA , Cléroux P , Gottschalk M . Streptococcus suis and group B Streptococcus differ in their interactions with murine macrophages . FEMS immunology and medical microbiology . 1998 Jul ; 21 ( 3 ): 189 – 95 . doi: 10.1111/j.1574-695X.1998.tb01165.x . PubMed PMID: 9718208 ; eng. OpenUrl CrossRef PubMed 61. ↵ Domenech M , García E , Moscoso M . Versatility of the capsular genes during biofilm formation by Streptococcus pneumoniae . Environmental microbiology . 2009 Oct ; 11 ( 10 ): 2542 – 55 . doi: 10.1111/j.1462-2920.2009.01979.x . PubMed PMID: 19549167 ; eng. OpenUrl CrossRef PubMed Web of Science 62. ↵ Wang S , Wang C , Gao L , et al. Rutin Inhibits Streptococcus suis Biofilm Formation by Affecting CPS Biosynthesis . Frontiers in pharmacology . 2017 ; 8 : 379 . doi: 10.3389/fphar.2017.00379 . PubMed PMID: 28670278 ; PubMed Central PMCID: PMCPMC5472726 . eng. OpenUrl CrossRef PubMed View the discussion thread. Back to top Previous Next Posted September 28, 2024. Download PDF Data/Code Email Thank you for your interest in spreading the word about bioRxiv. NOTE: Your email address is requested solely to identify you as the sender of this article. Your Email * Your Name * Send To * Enter multiple addresses on separate lines or separate them with commas. You are going to email the following Identification and characterization of ugpE required for the full virulence of Streptococcus suis Message Subject (Your Name) has forwarded a page to you from bioRxiv Message Body (Your Name) thought you would like to see this page from the bioRxiv website. Your Personal Message CAPTCHA This question is for testing whether or not you are a human visitor and to prevent automated spam submissions. Share Identification and characterization of ugpE required for the full virulence of Streptococcus suis Qiulei Yang , Na Li , Yanyan Tian , Qiao Liang , Miaomiao Zhao , Hong Chu , Yan Gong , Tong Wu , Shaopeng Wei , He Wang , Guangmou Yan , Fengyang Li , Liancheng Lei bioRxiv 2024.09.25.615082; doi: https://doi.org/10.1101/2024.09.25.615082 Share This Article: Copy Citation Tools Identification and characterization of ugpE required for the full virulence of Streptococcus suis Qiulei Yang , Na Li , Yanyan Tian , Qiao Liang , Miaomiao Zhao , Hong Chu , Yan Gong , Tong Wu , Shaopeng Wei , He Wang , Guangmou Yan , Fengyang Li , Liancheng Lei bioRxiv 2024.09.25.615082; doi: https://doi.org/10.1101/2024.09.25.615082 Citation Manager Formats BibTeX Bookends EasyBib EndNote (tagged) EndNote 8 (xml) Medlars Mendeley Papers RefWorks Tagged Ref Manager RIS Zotero Tweet Widget Facebook Like Google Plus One Subject Area Microbiology Subject Areas All Articles Animal Behavior and Cognition (7653) Biochemistry (17763) Bioengineering (13944) Bioinformatics (42100) Biophysics (21509) Cancer Biology (18667) Cell Biology (25588) Clinical Trials (138) Developmental Biology (13413) Ecology (19969) Epidemiology (2067) Evolutionary Biology (24393) Genetics (15647) Genomics (22581) Immunology (17791) Microbiology (40523) Molecular Biology (17222) Neuroscience (88860) Paleontology (667) Pathology (2848) Pharmacology and Toxicology (4841) Physiology (7668) Plant Biology (15182) Scientific Communication and Education (2048) Synthetic Biology (4312) Systems Biology (9843) Zoology (2274)