The percentage of average relative abundances of Methylobacterium sp. Oral Taxon C7, Methylobacterium sp. Oral Taxon B84, and Methylobacterium hispanicumand association with periodontal health and type 2 diabetes in a cohort of Sri Lankan men diagnosed with oral fibroepithelial polyps

The percentage of average relative abundances of Methylobacterium sp. Oral Taxon C7, Methylobacterium sp. Oral Taxon B84, and Methylobacterium hispanicumand association with periodontal health and type 2 diabetes in a cohort of Sri Lankan men diagnosed with oral fibroepithelial polyps | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (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],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article The percentage of average relative abundances of Methylobacterium sp. Oral Taxon C7, Methylobacterium sp. Oral Taxon B84, and Methylobacterium hispanicum and association with periodontal health and type 2 diabetes in a cohort of Sri Lankan men diagnosed with oral fibroepithelial polyps Manosha Lakmali Perera, Irosha Perera This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6945213/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Objectives: The present study aimed to assess the percentage of average relative abundances of Methylobacterium sp. Oral Taxon C7, Methylobacterium sp. Oral Taxon B84, and Methylobacterium hispanicum and their association with periodontal health and type 2 diabetes in a cohort of Sri Lankan men diagnosed with oral fibroepithelial polyps. Materials and methods: This retrospective study was based a representative sub-sample of 25 clinically diagnosed oral FEP (the control group) selected from a main case-control study. Amplification of nucle­otides of Extracted DNA from frozen tissues was subjected to nucleotide amplification for the V1 to V3 region. The amplified nucleotides were subjected to sequencing with Illumina’s 2X 300–bp chemistry. The high-quality nonchimeric merged reads were classified to the species level with a prior­itized BLASTN-based algorithm. A structured, pre-tested interviewer administered questionnaire was used to collect socio-demographics, oral risk habits, oral hygiene indicators and medical history data. The data were entered and analyzed using the SPSS 21 Statistical Package. Descriptive statistics were presented as percentage distributions. Fisher’s exact test compared groups with cell counts less than 5. Results: The percentage of average relative abundance of Methylobacterium sp . Oral Taxon C7 was 0.06%, followed by Methylobacterium sp. Oral Taxon B84 was 0.03% and Methylobacterium hispanicum was 0.01%. There was no statistically significant association between the percentage of average relative abundance of each Methylobacterium species with periodontal disease status and T2DM. Conclusion: Though , there are statistically significance associations this study highlights the need of powered cohort studies to find out possible associations of this nosocomial pathogen with periodontal disease status and T2DM. Introduction Methylobacterium species are ubiquitous in the environment and can survive and proliferate in vegetation, soil, dust, and freshwater [1, 2]. This bacterium is also a member of the human oral and feet microbiome [3]. Biofilms of this bacterium may form on different surfaces, including medical devices, water supply systems, or endoscope channels, and are highly resistant to disinfectants, high temperatures, and drying [2]. Resistance of M. mesophilicum to 2% glutaraldehyde has been reported [4]. It can contaminate medical devices: endoscopes, bronchoscopes, gastroscopes, ventilators, and catheters [2]. Methylobacterium species thrive in a wide range of aquatic environments, including our vital drinking water supplies and the tap water found in hospitals [5]. Alarmingly, they have also been detected in water used for dental procedures and in blood bank purification units [6,7]. Scientific research highlights their remarkable ability to form resilient biofilms [8, 9, 10]. which presents significant challenges for disinfection. In a pivotal study by Simões et al., [9] the effects of sodium hypochlorite (liquid bleach) on Methylobacterium biofilms were rigorously tested. The findings were revealing: while biofilms could recover their mass, activity, and viability after only one hour of exposure to a 0.01% concentration of sodium hypochlorite, a higher concentration of 0.1% was devastating, completely inactivating the bacteria in the biofilms within the same time frame. Moreover, these biofilms exhibit surprising resilience against various cleaning agents. For example, they were able to withstand 24 hours [8] of exposure to 1% benzalkonium chloride without losing viability. Their tolerance to drying is equally striking; even after ten days, the survival rate of Methylobacterium decreased by less than one log. Remarkably, some strains within these biofilms can survive and even show growth potential after enduring four weeks of desiccation without any nutrients. This evidence underscores the formidable nature of Methylobacterium biofilms and the urgent need for effective strategies to combat them in our water systems and healthcare environments [2]. The majority of Methylobacterium infections were healthcare-associated; two cases of bloodstream infections due to M. mesophilica were attributed to tap water used for oral irrigation for patients with mucositis as a complication after bone marrow transplantation [11]. Contaminated preservative fluid used for bone marrow harvesting was a possible source of Methylobacterium bacteremia in a patient receiving hematopoietic stem cell transplantation [12]. he contamination of stagnant bathroom water with Methylobacterium mesophilicum has emerged as a critical factor leading to recurrent peritonitis in patients undergoing continuous ambulatory peritoneal dialysis [13]. Environmental exposures, such as consuming raw vegetables, gardening, swimming in rivers, and coming into contact with soil, leaves, and flowers, have been linked to alarming cases of Methylobacterium infections in immuno compromised individuals [14]. The risk of these infections is heightened by conditions leading to immunosuppression, including hematological and solid malignancies, organ transplants, renal failure, HIV infections, tuberculosis, and alcoholism [2]. In the shed of light, our study seeks to uncover the vital connections between the average relative abundance of each bacterium, periodontal disease status, and type 2 diabetes mellitus. Understanding these relationships is essential for improving patient care and preventing serious health complications. Materials and Methods 2.1 Ethical approval Ethical approval for this study by the Faculty Research Committee of the Faculty of Dental Sciences at the University of Peradeniya, Sri Lanka (FRC/FDS/UOP/E/2014/32), and by the Griffith University Human Research Ethics Committee in Australia (DOH/18/14/HREC). Informed consent was obtained from each participant as previously described[15, 16]. 2.2 Study design, sample size calculation, setting and subjects This retrospective study was part of a multicenter field investigation. Nine Oral and Maxillo-Facial (OMF) Units across Sri Lanka were visited, representing six provinces: Western, Southern, Sabaragamuwa, North Western, Uva, and Central. A representative sub-sample of 25 clinically diagnosed Fibrous Epithelial Polyps (FEP) selected from the larger unmatched case-control study, which included 134 histologically confirmed cases of oral squamous cell carcinoma (OSCC,) and 134 clinically diagnosed benign mucosal lesions (BML) as controls, as previously described (15). The sample size for the unmatched case-control study was calculated using the formula established by Kelsey et al. [17]. The profile of the bacteriome included Sinhala participants aged 40 and older with a clinical diagnosis of FEP involving the buccal mucosa or tongue, who had not taken antibiotics in the past two months, as detailed earlier (15). This retrospective study was based on a multicenter field study Selected nine Oral and Maxillo-Facial (OMF) Units across Sri Lanka were visited, representing six provinces; namely, Western, Southern, Sabaragamuwa, North Western, Uva, and Central [15]. 2.2 Questioner Based Data collection A structured, pre-tested questionnaire to collect data through an interview administered by a trained interviewer. The questionnaire included both open-ended and closed-ended questions, which were broadly categorized to gather information on socio-demographics, oral risk habits, clinical oral indicators, family history, and the presence of non-communicable diseases other than oral cancer. The clinical oral examination was conducted by a Specialist in Dental Public Health, as previously described[15]. 2.3 Tissue Sample Collection After the excision of clinically diagnosed fibroepithelial polyps, about 3mm3 pieces were removed from an area deep to the center (depth) of the mass, avoiding the surface of the specimen and saliva as much as possible. Samples were stored as frozen tissues at = 80 0 C [15, 16]. 2.4 DNA Extraction Chopping of frozen tissue samples weighing approximately 100 mg was done using a sterile blade for each sample. DNA extraction was performed using the Gentra Puregene Tissue Kit (Qiagen, Hilden, Germany), following the manufacturer's instructions for the solid tissue protocol with two modifications: (1) the samples were incubated in the lysis buffer overnight and (2) an additional lysis step was included, utilizing 50 units of mutanolysin at 37°C for 1.5 hours to digest the cell walls of Gram-positive bacteria. This preparation was for the subsequent analysis of bacterial content. The DNA concentration and purity were measured using the Nano Drop™ 1000 Spectrophotometer (Thermo Fisher Scientific, Waltham, MA), and the extracted DNA was stored at –80°C as described previously [15, 16]. 2.5 Amplicon Library Preparation and Nucleotide Sequencing Prokaryotic primers 27FYM (5′-AGAGTTTGATCMTGGCT­CAG-3′) and 519R (5′-GW ATTACCGCGGCKGCTG3′), were used to amplify V1-V3 region of the 16S rRNA gene. Amplicon library preparation, indexing, and sequencing at the Aus­tralian Centre for Ecogenomics (University of Queensland, Australia. Specifically, 2×300–bp chemistry was used on a MiSeq platform (Illumina) for sequencing [15, 16]. 2.7 Nucleotide Sequencing Data Pre Processing Data preprocessing was conducted as previously described for prokaryotic raw sequencing reads [15, 16]. Reads with primer mismatches were removed. Then the primer sequences were trimmed off. The high-quality, non-chimeric merged reads were classified down to the species level using BLASTN searches against four databases of 16S rRNA prokaryotic gene reference sequences. This classification was based on alignment coverage and percentage identity of 98% or greater, as previously detailed [18]. 2.8 Compositional Analysis of the Bacteriome High-quality, non-chimeric sequences were meticulously classified at the species level using a powerful combination of two BLASTN-based algorithms, in line with cutting-edge research (29,30). Each read was carefully subjected to a BLASTN search, demanding an impressive alignment coverage and identity of ≥ 98% against four comprehensive sets of 16S rRNA reference sequences, prioritized as follows: the Human Oral Microbiome Database (HOMD) version 14.5; the chimera-free Human Oral Microbiome extended database (trusted-HOMDext); a refined version of the Green Gene Gold set (modified-GGG); and the NCBI’s Microbial 16S set (August 2016 release). Our approach began by ranking matches based on their relevance from HOMD version 14.5, emphasizing precision in classification. Sequences were classified at the species level by aligning with the taxonomy of the sequence that exhibited the highest percentage identity and bit score (the hit reference sequence) from the most prioritized reference set. For instances where reads returned top hits across multiple species, we conducted a secondary de novo chimera check using the highly reliable USEARCH tool. Singleton operational taxonomic units (OTUs) were excluded to maintain focus on significant results, and a representative sequence from each remaining OTU underwent another round of BLASTN searching against the four reference sets to ascertain the closest species, ensuring accurate taxonomy assignment, as shown in previous studies (27). To facilitate thorough downstream analysis and uniform sub-sampling, we employed the QIIME (Quantitative Insights Into Microbial Ecology) software package, version 1.9.1 (530). This methodical approach enabled us to standardize the number of reads across all samples, allowing for a precise calculation of the average relative abundance percentage for each taxon, as previously outlined (27). By implementing these rigorous techniques, we significantly enhance the reliability of our findings, paving the way for groundbreaking insights into microbial ecology. 2.9 Analysis of Questioner based Data Data were meticulously entered and analyzed using the SPSS 21 Statistical Package, ensuring a rigorous assessment of our findings. We present descriptive statistics as percentage distributions, providing clear insights into our data. For groups with cell counts below 5, we utilized Fisher's exact test to ensure accurate comparisons. This comprehensive analysis zeroes in on critical health factors: periodontal disease status, diabetes, betel quid chewing, smoking, and alcohol consumption. We compared two groups based on their average relative abundance of the Methylobacterium species group — one group with levels below the average and the other with levels at or above the average. By doing so, we aim to uncover meaningful relationships that could drive health interventions and improve patient outcomes. Results This retrospective study is based on a subset of patients diagnosed with oral fibroepithelial polyps (FEP) in Sri Lanka by carefully selecting 25 individuals from a larger cohort. Our investigation focuses on the prevalence nosocomial pathogens, specifically Methylobacterium sp. Oral Taxon C7 , Methylobacterium sp. Oral Taxon B84 , and Methylobacterium hispanicum , within FEP tissues. What sets this study apart is its goal to analyze how the detection of these Methylobacterium s pecies relates to the average relative abundance in the context of periodontal disease and diabetes. Understanding these correlations is essential, as it may illuminate overlooked connections that could lead to better management strategies for patients with oral FEP. Join us as we explore these vital relationships that could significantly impact clinical practice and improve patient outcomes. 3.1 Detection levels of Methylobacterium sp. Oral Taxon C7, Methylobacterium sp. Oral Taxon B84, and Methylobacterium hispanicum in a cohort of Sri Lankan men diagnosed with oral fibroepithelial polyps Table 01: The frequency of distribution of the detection of Methylobacterium sp . Oral Taxon C7 in FEP tissues equal to or more than, and less than the average relative abundance Variable Frequency % Less than the percentage of average relative abundance, 0.06% (<) of Methylobacterium sp. Oral Taxon C7 . 24 96 Equal or more than the percentage of average relative abundance 0.06% (≥)of Methylobacterium sp. Oral Taxon C7 01 04 Total 25 100.0 Less than the percentage of average relative abundance, 0.03% (<)of Methylobacterium sp. Oral Taxon B84 24 96 Equal or more than the percentage of average relative abundance, 0.03% (≥)of Methylobacterium sp. Oral Taxon B84 01 4 Total 25 100 Less than the percentage of average relative abundance, 0.01% (<) of Methylobacterium hispanicum 24 96 Equal or more than the percentage of average relative abundance, 0.01% (≥)of Methylobacterium hispanicum 01 04 Total 25 100.0 According to Table 1, each Methylobacterium species was detected in the same level. Of them, 96% detected < the % average relative abundance and 4% detected ≥ the % average relative abundance. 3.2 The Socio-demographic Profile Table02: The socio-demographic profile of a subset of group of oral fibroepithelial polyp patients in Sri Lanka. Variable Subjects n=25 Age mean ± SD in years 49.56 ± 13.38 Gender Male N % 25 (100.0) Level of Education N % No Schooling Grade 1-5 Grade 6-10 GCE O/L GCE A/L 1 (4.0) 4 (16.0) 10 (40.0) 4 (16.0) 6 (24.0) Total 25 (100.0) Table 02 demonstrates the socio-demographic profile of FEP subjects. Accordingly, the mean ± SD age of cases was 49.56 ± 13.38 years. Moreover, the highest percentage 10 (40.0%) of FEP attended school in grades 6-10, and the least 1 (4.0%) did not attend school. However, 6 (24.0) % of them accomplished secondary education with GCE A/L. 3.3 Methylobacterium species and periodontal diseases Table03: Distribution of periodontal disease status with the detection of Methylobacterium species in FEP tissues equal to more than, and less than the percentage of average relative abundance. Detection of Methylobacterium species Periodontal disease status Mild Moderate Severe N % N % N% Total p value Less than the percentage of average relative abundance (0.05) Equal or more than the percentage of average relative abundance (≥) 01 (33.33) 01(33.33) 01(33.33) 03 (22.0) Total 17 (68.0) 06(24.0) 02 (8.0) 25 (100.0) *Fisher’s exact test for statistical significance to compare groups (cell counts < 5). Table 2 presents the severity of periodontal disease status with the detection of Methylobacterium species. Accordingly, the overwhelming majority of 16 (72.72) % of oral FEP patients with < than the percentage of average relative abundance of this opportunistic pathogen were mild, followed by 05 (22.73) % of moderate and 01(04.55) % of severe when it comes to periodontal disease status. However, there was no statistically significant difference between these two groups (p>0.05) as (p=0.097) in this scenario. 3.3 Methylobacterium species and type 2 Diabetes Mellitus Table 3: Distribution of Type 2 diabetes mellitus with the detection of Methylobacterium species in FEP tissues equal to more than, and less than the percentage of average relative abundance Detection of Methylobacterium species T2DM No % Yes % Total p value Less than the percentage of average relative abundance (0.05) Equal or more than the percentage of average relative abundance (≥) 03 (100.0) 00 (0.00) 03 (12.0) Total 22 (88.0 ) 03 (12.0) 25 (100.0) *Fisher’s exact test for statistical significance to compare groups (cell counts < 5). As demonstrated in Table 3, 03 (13.64 %) of oral FEP patients with Methylobacterium species less than the percentage of average relative abundance (<) were diabetics. In contrast, 0 (0.00%) of diabetics harbored Methylobacterium species equal to or more than the percentage of average relative abundance (≥). Nevertheless, these two groups' differences were not statistically significant (p>0.05). Discussion This study represents a groundbreaking contribution to our understanding of Methylobacterium species in Sri Lanka, being the first to document their presence in male patients with oral fibroepithelial polyps. The scarcity of similar research in both the national and regional contexts underscores the novelty and importance of our findings. Additionally, there are very few international studies available for comparison, making our results even more significant. Our research revealed a striking detection rate of Methylobacterium species in the fibroepithelial polyp tissues of Sri Lankan males, with 24 samples showing a significant relative abundance of 96% and 4 samples indicating 1% or more. These results resonate with earlier findings by Carvajal and colleagues in 2011 [3], who identified Methylobacterium zatmanii , a pink pigmented facultative methylotrophs, in the oral cavity of a male patient suffering from periodontitis and dental caries. Moreover, our work builds upon the foundational studies by Anesti and colleagues in 2005[19], who explored the isolation and molecular detection of methylotrophic bacteria in the human mouth. In the present study , Methylobacterium sp. Oral Taxon C7, Methylobacterium sp. Oral Taxon B84, and Methylobacterium hispanicum identified as the most abundant Methylobacterium species of the oral cavity of Sri Lankan males with FEPs. In contrast, novel Methylobacterium brachiatum was isolated from human skin in a study conducted by Cremers and Colleagues [23]. Though we have not detected, M. extorquens demonstrates a remarkable capacity for biofilm formation, achieving peak biofilm levels and metabolic activity after just 7 days in R2A broth. While the application of a 1% peracetic acid disinfectant significantly hinders the growth of M. extorquens in 2-, 5-, and 7-day biofilms immediately following treatment, the challenge remains. Regrowth of these resilient biofilms was observed after a further 7 days in R2A broth, particularly when the critical drying step was omitted post-disinfection. In stark contrast, implementing the drying procedure effectively eliminated any signs of regrowth. This study powerfully illustrates not only the limitations of peracetic acid in combating M. extorquens biofilms but also the critical importance of including a drying phase in disinfection protocols. Adopting this combined approach will significantly enhance the management of Methylobacterium in biofilms, ensuring more effective results [2]. Monitoring water sources in healthcare institutions is crucial for preventing and controlling nosocomial infections caused by opportunistic pathogens. Automated endoscope reprocessors (AERs) can become contaminated when non-sterile water is used for rinsing [24,25,26].The frequent occurrence and colonization of Methylobacterium in hospital environments can be attributed to its high resistance to dehydration and chlorination, tolerance to elevated temperatures, slow growth, and ability to form biofilms. The mean age of these patients was 49.56 ± 13.38 years and the majority was qualified from A/Levels, We have not found statistically significant associations between the detection levels of Methylobacterium species with periodontal disease status and type 2 diabetes mellitus. However, the small sample size is a limitation of our study. Nevertheless, the implications of our findings could pave the way for future research and highlight the need for further exploration of microbial influences on oral health in Sri Lanka and beyond with powered cohort studies. Declarations Acknowledgements: We acknowledge late Professor Newell Johnson, Associate Professor Glen Ulett, Professor of Microbiology, School of Medical Science and Pharmacy, Gold Coast Campus, Griffith University, QLD 4222, Dr. Deepak Ipe and Dr. DJ Speicher for their valuable contribution to make this study success. We extended our gratitude to Prof. WM Tilakaratne, Senior Professor of Oral Pathology, and Prof. L. Samaranayake Professor of Oral Microbiology for their guidance. We thank Oral and Maxillo-Facial Surgeons Dr. Sharika Gunathilake, Dr. S.A.K.J. Kumara, Dr. Ranjith Lal Kandewatte, Dr. P. Kirupakaran, Dr. D.K. Dias, Dr. Chamara Athukorale, Dr. Suresh Shanmuganathan, and Dr. T. Sabesan for facilitating data and sample collection from their respective Oral and Maxillo-Facial Units. Conflict of interest: No potential conflict of interest was reported by the authors. Sources of finding: This study is funded by Griffith University International Postgraduate Research Scholarship (GUIPRS) 2012, Grant No: MSC 1010,class H,MPP and self-finance (M.P. and I.P.) References Vaneechoutte M, Dijkshoorn L, Nemec A, Kämpfer P, Wauters G (2011) Acinetobacter , Chryseobacterium , Moraxella , and other nonfermentative Gram-negative rods. In: Versalovic J, Carroll KC, Jorgensen JH, Funke G, Landry ML, Warnock DW (eds) Manual of clinicalmicrobiology10th ed, vol 1. ASM, Washington, DC, pp 729–731. In Kovaleva J, Degener JE, van der Mei HC (2014) Methylobacterium and its role in health care-associated infection. J Clin Microbiol. ;52(5):1317-21. doi: 10.1128/JCM.03561-13. Epub 2014 Jan 15. PMID: 24430456; PMCID: PMC3993692 Carvajal TM, Tan R, Lee AC (2011) A pink pigmented facultative methylotrophic (PPFM)bacterium isolated from the human oral cavity. 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University of Groningen, Groningen, the Netherlands Cremers G, Kenyon A, Gubbels N, Jansen M, van Alen TA, Berben T, Op den Camp HJM (2020) Draft genome sequence of a novel Methylobacterium brachiatum strain isolated from human skin. Microbiol Resour Announc 9:e01093–e01020. https://doi.org/10.1128/MRA01093-20 Gilchrist MJ, Kraft JA, Hammond JG, Connelly BL, Myers MG (1986) Detection of Pseudomonas mesophilica as a source of nosocomial infections in a bone marrow transplant unit. J Clin Microbiol 23:1052–1055 Brown MA, Greene JN, Sandin RL, Hiemenz JW, Sinnott JT (1996) Methylobacterium bacteremia after infusion of contaminated autologous bone marrow. Clin Infect Dis 23:1191–1192. http://dx.doi.org/10.1093/clinids/23.5.1191 Rutherford PC, Narkowicz JE, Wood CJ, Peel MM (1988) Peritonitis caused by Pseudomonas mesophilica in a patient undergoing continuous ambulatory peritoneal dialysis. J Clin Microbiol 26:2441–2443 Additional Declarations The authors declare no competing interests. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6945213","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":474471402,"identity":"6b38dc3c-3d04-400a-a881-ae157a377f5e","order_by":0,"name":"Manosha Lakmali Perera","email":"data:image/png;base64,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","orcid":"","institution":"Griffith University Australia (Alumnus)","correspondingAuthor":true,"prefix":"","firstName":"Manosha","middleName":"Lakmali","lastName":"Perera","suffix":""},{"id":474471403,"identity":"884d9d6f-33e1-4ba8-9747-b80335b88945","order_by":1,"name":"Irosha Perera","email":"","orcid":"","institution":"National Dental Hospital, Teaching, Colombo07","correspondingAuthor":false,"prefix":"","firstName":"Irosha","middleName":"","lastName":"Perera","suffix":""}],"badges":[],"createdAt":"2025-06-21 13:25:58","currentVersionCode":1,"declarations":{"humanSubjects":false,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-6945213/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6945213/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":85289652,"identity":"ab05deb3-9589-45d4-b5fa-8c78dd6c8e67","added_by":"auto","created_at":"2025-06-24 09:46:08","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1007349,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6945213/v1/ff480117-053c-4fe9-be72-0f7f4b825524.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eThe percentage of average relative abundances of \u003c/strong\u003e\u003cem\u003e\u003cstrong\u003eMethylobacterium sp. Oral Taxon C7, Methylobacterium sp. Oral Taxon B84, and Methylobacterium hispanicum\u003c/strong\u003e\u003c/em\u003e\u003cstrong\u003eand association with periodontal health and type 2 diabetes in a cohort of Sri Lankan men diagnosed with oral fibroepithelial polyps\u003c/strong\u003e\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003e\u003cem\u003eMethylobacterium\u003c/em\u003e species are ubiquitous in the environment and can survive and proliferate in vegetation, soil, dust, and freshwater [1, 2]. \u0026nbsp;This bacterium is also a member of the human oral and feet microbiome [3]. Biofilms of this bacterium may form on different surfaces, including medical devices, water supply systems, or endoscope channels, and are highly resistant to disinfectants, high temperatures, and drying [2]. Resistance of \u003cem\u003eM. mesophilicum\u0026nbsp;\u003c/em\u003eto 2% glutaraldehyde has been reported [4]. It can contaminate medical devices: endoscopes, bronchoscopes, gastroscopes, ventilators, and catheters [2].\u003c/p\u003e\n\u003cp\u003eMethylobacterium species thrive in a wide range of aquatic environments, including our vital drinking water supplies and the tap water found in hospitals [5]. \u0026nbsp;Alarmingly, they have also been detected in water used for dental procedures and in blood bank purification units [6,7]. Scientific research highlights their remarkable ability to form resilient biofilms [8, 9, 10]. which presents significant challenges for disinfection. In a pivotal study by Simões et al., [9] the effects of sodium hypochlorite (liquid bleach) on Methylobacterium biofilms were rigorously tested. The findings were revealing: while biofilms could recover their mass, activity, and viability after only one hour of exposure to a 0.01% concentration of sodium hypochlorite, a higher concentration of 0.1% was devastating, completely inactivating the bacteria in the biofilms within the same time frame. Moreover, these biofilms exhibit surprising resilience against various cleaning agents. For example, they were able to withstand 24 hours [8] of exposure to 1% benzalkonium chloride without losing viability. Their tolerance to drying is equally striking; even after ten days, the survival rate of Methylobacterium decreased by less than one log. Remarkably, some strains within these biofilms can survive and even show growth potential after enduring four weeks of desiccation without any nutrients. This evidence underscores the formidable nature of \u003cem\u003eMethylobacterium\u003c/em\u003e biofilms and the urgent need for effective strategies to combat them in our water systems and healthcare environments [2].\u003c/p\u003e\n\u003cp\u003eThe majority of \u003cem\u003eMethylobacterium\u003c/em\u003e infections were healthcare-associated; two cases of bloodstream infections due to \u003cem\u003eM. mesophilica\u003c/em\u003e were attributed to tap water used for oral irrigation for patients with mucositis as a complication after bone marrow transplantation [11]. Contaminated preservative fluid used for bone marrow harvesting was a possible source of \u003cem\u003eMethylobacterium\u0026nbsp;\u003c/em\u003ebacteremia in a patient receiving hematopoietic stem cell transplantation [12].\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ehe contamination of stagnant bathroom water with \u003cem\u003eMethylobacterium \u0026nbsp;mesophilicum\u003c/em\u003e has emerged as a critical factor leading to recurrent peritonitis in patients undergoing continuous ambulatory peritoneal dialysis [13]. Environmental exposures, such as consuming raw vegetables, gardening, swimming in rivers, and coming into contact with soil, leaves, and flowers, have been linked to alarming cases of \u003cem\u003eMethylobacterium\u003c/em\u003e infections in immuno compromised individuals [14]. The risk of these infections is heightened by conditions leading to immunosuppression, including hematological and solid malignancies, organ transplants, renal failure, HIV infections, tuberculosis, and alcoholism [2]. In the shed of light, our study seeks to uncover the vital connections between the average relative abundance of each bacterium, periodontal disease status, and type 2 diabetes mellitus. Understanding these relationships is essential for improving patient care and preventing serious health complications.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003e\u003cstrong\u003e2.1 Ethical approval\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEthical approval for this study by the Faculty Research Committee of the Faculty of Dental Sciences at the University of Peradeniya, Sri Lanka (FRC/FDS/UOP/E/2014/32), and by the Griffith University Human Research Ethics Committee in Australia (DOH/18/14/HREC). Informed consent was obtained from each participant as previously described[15, 16].\u003c/p\u003e\n\u003cp\u003e2.2 Study design, sample size calculation, setting and subjects\u003c/p\u003e\n\u003cp\u003eThis retrospective study was part of a multicenter field investigation. Nine Oral and Maxillo-Facial (OMF) Units across Sri Lanka were visited, representing six provinces: Western, Southern, Sabaragamuwa, North Western, Uva, and Central. A representative sub-sample of 25 clinically diagnosed Fibrous Epithelial Polyps (FEP) selected from the larger unmatched case-control study, which included 134 histologically confirmed cases of oral squamous cell carcinoma (OSCC,) and 134 clinically diagnosed benign mucosal lesions (BML) as controls, as previously described (15). The sample size for the unmatched case-control study was calculated using the formula established by Kelsey et al. [17]. The profile of the bacteriome included Sinhala participants aged 40 and older with a clinical diagnosis of FEP involving the buccal mucosa or tongue, who had not taken antibiotics in the past two months, as detailed earlier (15).\u003c/p\u003e\n\u003cp\u003eThis retrospective study was based on a multicenter field study Selected nine Oral and Maxillo-Facial (OMF) Units across Sri Lanka were visited, representing six provinces; namely, Western, Southern, Sabaragamuwa, North Western, Uva, and Central [15].\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2\u0026nbsp;\u0026nbsp; \u0026nbsp; \u0026nbsp;Questioner Based Data collection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA structured, pre-tested questionnaire to collect data through an interview administered by a trained interviewer. The questionnaire included both open-ended and closed-ended questions, which were broadly categorized to gather information on socio-demographics, oral risk habits, clinical oral indicators, family history, and the presence of non-communicable diseases other than oral cancer. The clinical oral examination was conducted by a Specialist in Dental Public Health, as previously described[15].\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.3\u0026nbsp;Tissue Sample Collection\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAfter the excision of clinically diagnosed fibroepithelial polyps, about 3mm3 pieces were removed from an area deep to the center (depth) of the mass, avoiding the surface of the specimen and saliva as much as possible. Samples were stored as frozen tissues at = 80\u003csup\u003e0\u003c/sup\u003eC [15, 16].\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.4\u0026nbsp;DNA Extraction \u0026nbsp;\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eChopping of frozen tissue samples weighing approximately 100 mg was done using a sterile blade for each sample. DNA extraction was performed using the Gentra Puregene Tissue Kit (Qiagen, Hilden, Germany), following the manufacturer's instructions for the solid tissue protocol with two modifications: (1) the samples were incubated in the lysis buffer overnight and (2) an additional lysis step was included, utilizing 50 units of mutanolysin at 37°C for 1.5 hours to digest the cell walls of Gram-positive bacteria. This preparation was for the subsequent analysis of bacterial content. The DNA concentration and purity were measured using the Nano Drop™ 1000 Spectrophotometer (Thermo Fisher Scientific, Waltham, MA), and the extracted DNA was stored at –80°C as described previously [15, 16].\u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.5\u0026nbsp;Amplicon Library Preparation and Nucleotide Sequencing\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eProkaryotic primers 27FYM (5′-AGAGTTTGATCMTGGCT­CAG-3′) and 519R (5′-GW ATTACCGCGGCKGCTG3′), were used to amplify V1-V3 region of the 16S rRNA gene. Amplicon library preparation, indexing, and sequencing at the Aus­tralian Centre for Ecogenomics (University of Queensland, Australia. Specifically, 2×300–bp chemistry was used on a MiSeq platform (Illumina) for sequencing [15, 16].\u003c/p\u003e\n\u003cp\u003e2.7 \u0026nbsp; \u0026nbsp;Nucleotide Sequencing Data Pre Processing\u003c/p\u003e\n\u003cp\u003eData preprocessing was conducted as previously described for prokaryotic raw sequencing reads [15, 16]. Reads with primer mismatches were removed. Then the primer sequences were trimmed off. The high-quality, non-chimeric merged reads were classified down to the species level using BLASTN searches against four databases of 16S rRNA prokaryotic gene reference sequences. This classification was based on alignment coverage and percentage identity of 98% or greater, as previously detailed [18].\u003c/p\u003e\n\u003cp\u003e2.8 \u0026nbsp; \u0026nbsp;Compositional Analysis of the Bacteriome\u003c/p\u003e\n\u003cp\u003eHigh-quality, non-chimeric sequences were meticulously classified at the species level using a powerful combination of two BLASTN-based algorithms, in line with cutting-edge research (29,30). Each read was carefully subjected to a BLASTN search, demanding an impressive alignment coverage and identity of ≥ 98% against four comprehensive sets of 16S rRNA reference sequences, prioritized as follows: the Human Oral Microbiome Database (HOMD) version 14.5; the chimera-free Human Oral Microbiome extended database (trusted-HOMDext); a refined version of the Green Gene Gold set (modified-GGG); and the NCBI’s Microbial 16S set (August 2016 release). Our approach began by ranking matches based on their relevance from HOMD version 14.5, emphasizing precision in classification. Sequences were classified at the species level by aligning with the taxonomy of the sequence that exhibited the highest percentage identity and bit score (the hit reference sequence) from the most prioritized reference set. For instances where reads returned top hits across multiple species, we conducted a secondary de novo chimera check using the highly reliable USEARCH tool. Singleton operational taxonomic units (OTUs) were excluded to maintain focus on significant results, and a representative sequence from each remaining OTU underwent another round of BLASTN searching against the four reference sets to ascertain the closest species, ensuring accurate taxonomy assignment, as shown in previous studies (27). To facilitate thorough downstream analysis and uniform sub-sampling, we employed the QIIME (Quantitative Insights Into Microbial Ecology) software package, version 1.9.1 (530). This methodical approach enabled us to standardize the number of reads across all samples, allowing for a precise calculation of the average relative abundance percentage for each taxon, as previously outlined (27). By implementing these rigorous techniques, we significantly enhance the reliability of our findings, paving the way for groundbreaking insights into microbial ecology.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.9 \u0026nbsp; \u0026nbsp;Analysis of Questioner based Data \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData were meticulously entered and analyzed using the SPSS 21 Statistical Package, ensuring a rigorous assessment of our findings. We present descriptive statistics as percentage distributions, providing clear insights into our data. For groups with cell counts below 5, we utilized Fisher's exact test to ensure accurate comparisons. This comprehensive analysis zeroes in on critical health factors: periodontal disease status, diabetes, betel quid chewing, smoking, and alcohol consumption. We compared two groups based on their average relative abundance of the Methylobacterium species group — one group with levels below the average and the other with levels at or above the average. By doing so, we aim to uncover meaningful relationships that could drive health interventions and improve patient outcomes.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThis retrospective study is based on a subset of patients diagnosed with oral fibroepithelial polyps (FEP) in Sri Lanka by carefully selecting 25 individuals from a larger cohort. Our investigation focuses on the prevalence nosocomial pathogens, \u0026nbsp;specifically \u003cem\u003eMethylobacterium sp. Oral Taxon\u003c/em\u003e \u003cem\u003eC7\u003c/em\u003e, \u003cem\u003eMethylobacterium sp. Oral Taxon B84\u003c/em\u003e, and \u003cem\u003eMethylobacterium hispanicum\u003c/em\u003e, within FEP tissues. What sets this study apart is its goal to analyze how the detection of these \u003cem\u003eMethylobacterium s\u003c/em\u003epecies relates to the average relative abundance in the context of periodontal disease and diabetes. Understanding these correlations is essential, as it may illuminate overlooked connections that could lead to better management strategies for patients with oral FEP. Join us as we explore these vital relationships that could significantly impact clinical practice and improve patient outcomes.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.1 Detection levels of \u003cem\u003eMethylobacterium sp. Oral Taxon C7, Methylobacterium sp. Oral Taxon B84, and Methylobacterium hispanicum\u003c/em\u003e in a cohort of Sri Lankan men diagnosed with oral fibroepithelial polyps\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 01: \u0026nbsp;The frequency of distribution of the detection of \u003cem\u003eMethylobacterium sp\u003c/em\u003e\u003cstrong\u003e.\u0026nbsp;\u003c/strong\u003e\u003cem\u003eOral Taxon C7\u0026nbsp;\u003c/em\u003ein FEP tissues equal to or more than, and less than the average relative abundance\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"644\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eFrequency\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e%\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eLess than the percentage of average relative abundance, 0.06% (\u0026lt;) of \u003cstrong\u003e\u003cem\u003eMethylobacterium sp. Oral Taxon C7\u003c/em\u003e\u003c/strong\u003e.\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e96\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eEqual or more than the percentage of average relative abundance 0.06% \u0026nbsp; (\u0026ge;)of \u003cstrong\u003e\u003cem\u003eMethylobacterium sp. Oral Taxon C7\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;04\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e25\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e100.0\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eLess than the percentage of average relative abundance, 0.03% (\u0026lt;)of \u003cstrong\u003e\u003cem\u003eMethylobacterium sp. Oral Taxon B84\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e96\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eEqual or more than the percentage of average relative abundance, 0.03% \u0026nbsp;(\u0026ge;)of \u003cstrong\u003e\u003cem\u003eMethylobacterium sp. Oral Taxon B84\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e25\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e100\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eLess than the percentage of average relative abundance, 0.01% (\u0026lt;) of \u003cstrong\u003e\u003cem\u003eMethylobacterium hispanicum\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e96\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eEqual or more than the percentage of average relative abundance, 0.01% (\u0026ge;)of \u003cstrong\u003e\u003cem\u003eMethylobacterium hispanicum\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e04\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e25\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e100.0\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAccording to Table 1, each Methylobacterium species was detected in the same level. Of them, 96% detected \u0026lt; the % average relative abundance and 4% detected \u0026ge; the % average relative abundance.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.2 The Socio-demographic Profile\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable02:\u0026nbsp;\u003c/strong\u003eThe socio-demographic profile of a subset of group of oral fibroepithelial polyp patients in Sri Lanka.\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"335\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;Subjects n=25\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eAge mean \u0026plusmn; SD in years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;49.56 \u0026plusmn; 13.38\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eGender\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;N \u0026nbsp; \u0026nbsp; %\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;25 (100.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eLevel of Education\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; N \u0026nbsp; \u0026nbsp; \u0026nbsp;%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eNo Schooling\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eGrade 1-5\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eGrade 6-10\u003c/p\u003e\n \u003cp\u003eGCE O/L\u003c/p\u003e\n \u003cp\u003eGCE A/L\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 1 \u0026nbsp; \u0026nbsp; (4.0)\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 4 \u0026nbsp; \u0026nbsp; (16.0)\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;10 (40.0)\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 4 \u0026nbsp; \u0026nbsp; (16.0)\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 6 \u0026nbsp; \u0026nbsp; (24.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; 25 (100.0)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u0026nbsp;Table 02 demonstrates the socio-demographic profile of FEP subjects. Accordingly, the mean \u0026plusmn; SD age of cases was 49.56 \u0026plusmn; 13.38 years. Moreover, the highest percentage 10 (40.0%) of FEP attended school in grades 6-10, and the least 1 (4.0%) did not attend school. However, 6 (24.0) % of them accomplished secondary education with GCE A/L.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.3 \u0026nbsp; \u003cem\u003eMethylobacterium\u003c/em\u003e species and periodontal diseases\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable03:\u0026nbsp;\u003c/strong\u003eDistribution of periodontal disease status with the detection of \u003cem\u003eMethylobacterium\u003c/em\u003e species in FEP tissues equal to more than, and less than the percentage of average relative abundance.\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"641\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 35.9621%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDetection of \u003cem\u003eMethylobacterium\u003c/em\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;species \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48.4227%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; Periodontal disease status \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; Mild \u0026nbsp; \u0026nbsp; \u0026nbsp;Moderate \u0026nbsp; Severe \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp;N % \u0026nbsp; \u0026nbsp; \u0026nbsp; N % \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; N% \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.6151%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal \u0026nbsp; \u0026nbsp; \u0026nbsp; p value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 35.9621%;\"\u003e\n \u003cp\u003eLess than the percentage of average relative abundance (\u0026lt;)\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48.4227%;\"\u003e\n \u003cp\u003e\u0026nbsp;16 (72.72) \u0026nbsp;05(22.73 ) 01(4.55)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.6151%;\"\u003e\n \u003cp\u003e\u0026nbsp;22 (88.0) \u0026nbsp; \u0026nbsp;\u0026nbsp;\u0026nbsp;*1.000 (p\u0026gt;0.05)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 35.9621%;\"\u003e\n \u003cp\u003eEqual or more than the percentage of average relative abundance (\u0026ge;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48.4227%;\"\u003e\n \u003cp\u003e\u0026nbsp;01 (33.33) \u0026nbsp; \u0026nbsp; 01(33.33) \u0026nbsp;01(33.33)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.6151%;\"\u003e\n \u003cp\u003e03 (22.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 35.9621%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 48.4227%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e17 (68.0) \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;06(24.0) \u0026nbsp; \u0026nbsp; 02 (8.0)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15.6151%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e25 (100.0)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e*Fisher\u0026rsquo;s exact test for statistical significance to compare groups (cell counts \u0026lt; 5).\u003c/p\u003e\n\u003cp\u003eTable 2 presents the severity of periodontal disease status with the detection of \u003cem\u003eMethylobacterium\u003c/em\u003e species. Accordingly, the overwhelming majority of 16 (72.72) % of oral FEP patients with \u0026lt; than the percentage of average relative abundance of this opportunistic pathogen were mild, followed by 05 (22.73) % of moderate and 01(04.55) % of severe when it comes to periodontal disease status. However, there was no statistically significant difference between these two groups (p\u0026gt;0.05) as (p=0.097) in this scenario.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.3 \u0026nbsp;\u003cem\u003eMethylobacterium\u003c/em\u003e species and type 2 Diabetes Mellitus\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3:\u0026nbsp;\u003c/strong\u003eDistribution of Type 2 diabetes mellitus with the detection of \u003cem\u003eMethylobacterium\u003c/em\u003e species in FEP tissues equal to more than, and less than the percentage of average relative abundance\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"642\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 38.5621%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDetection of\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eMethylobacterium species\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44.6078%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; T2DM\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp;No \u0026nbsp; % \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Yes \u0026nbsp;% \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16.8301%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;p value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 38.5621%;\"\u003e\n \u003cp\u003eLess than the percentage of average relative abundance (\u0026lt;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44.6078%;\"\u003e\n \u003cp\u003e\u0026nbsp;19 (86.36) \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;03 (13.64)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16.8301%;\"\u003e\n \u003cp\u003e22 (88.0) \u0026nbsp;\u0026nbsp;\u0026nbsp; \u0026nbsp;\u0026nbsp;*1.000 (p\u0026gt;0.05)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 38.5621%;\"\u003e\n \u003cp\u003eEqual or more than the percentage of average relative abundance (\u0026ge;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44.6078%;\"\u003e\n \u003cp\u003e\u0026nbsp;03 \u0026nbsp;(100.0) \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;00 (0.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16.8301%;\"\u003e\n \u003cp\u003e03 (12.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 38.5621%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 44.6078%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;22 (88.0 ) \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 03 (12.0)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16.8301%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;25 (100.0)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e*Fisher\u0026rsquo;s exact test for statistical significance to compare groups (cell counts \u0026lt; 5).\u003c/p\u003e\n\u003cp\u003eAs demonstrated in Table 3, 03 (13.64 %) of oral FEP patients with \u003cem\u003eMethylobacterium\u003c/em\u003e species less than the percentage of average relative abundance (\u0026lt;) were diabetics. In contrast, 0 (0.00%) of diabetics harbored \u003cem\u003eMethylobacterium\u003c/em\u003e species equal to or more than the percentage of average relative abundance (\u0026ge;). Nevertheless, these two groups\u0026apos; differences were not statistically significant (p\u0026gt;0.05).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study represents a groundbreaking contribution to our understanding of Methylobacterium species in Sri Lanka, being the first to document their presence in male patients with oral fibroepithelial polyps. The scarcity of similar research in both the national and regional contexts underscores the novelty and importance of our findings. Additionally, there are very few international studies available for comparison, making our results even more significant. Our research revealed a striking detection rate of Methylobacterium species in the fibroepithelial polyp tissues of Sri Lankan males, with 24 samples showing a significant relative abundance of 96% and 4 samples indicating 1% or more. These results resonate with earlier findings by Carvajal and colleagues in 2011 [3], who identified \u003cem\u003eMethylobacterium zatmanii\u003c/em\u003e, a pink pigmented facultative methylotrophs, in the oral cavity of a male patient suffering from periodontitis and dental caries. Moreover, our work builds upon the foundational studies by Anesti and colleagues in 2005[19], who explored the isolation and molecular detection of methylotrophic bacteria in the human mouth. In the present study\u003cstrong\u003e\u003cem\u003e,\u0026nbsp;\u003c/em\u003e\u003c/strong\u003e\u003cem\u003eMethylobacterium sp. Oral Taxon C7, Methylobacterium sp. Oral Taxon B84, and Methylobacterium hispanicum identified as the most abundant Methylobacterium species of the oral cavity of Sri Lankan males\u003c/em\u003e with FEPs. In contrast, novel \u003cem\u003eMethylobacterium brachiatum\u003c/em\u003e was isolated from human skin in a study conducted by Cremers and Colleagues [23].\u003c/p\u003e\n\u003cp\u003eThough we have not detected, \u003cem\u003eM. extorquens\u003c/em\u003e demonstrates a remarkable capacity for biofilm formation, achieving peak biofilm levels and metabolic activity after just 7 days in R2A broth. While the application of a 1% peracetic acid disinfectant significantly hinders the growth of M. extorquens in 2-, 5-, and 7-day biofilms immediately following treatment, the challenge remains. Regrowth of these resilient biofilms was observed after a further 7 days in R2A broth, particularly when the critical drying step was omitted post-disinfection. In stark contrast, implementing the drying procedure effectively eliminated any signs of regrowth. This study powerfully illustrates not only the limitations of peracetic acid in combating \u003cem\u003eM. extorquens\u003c/em\u003e biofilms but also the critical importance of including a drying phase in disinfection protocols. Adopting this combined approach will significantly enhance the management of \u003cem\u003eMethylobacterium\u0026nbsp;\u003c/em\u003ein biofilms, ensuring more effective results [2]. Monitoring water sources in healthcare institutions is crucial for preventing and controlling nosocomial infections caused by opportunistic pathogens. Automated endoscope reprocessors (AERs) can become contaminated when non-sterile water is used for rinsing [24,25,26].The frequent occurrence and colonization of Methylobacterium in hospital environments can be attributed to its high resistance to dehydration and chlorination, tolerance to elevated temperatures, slow growth, and ability to form biofilms.\u003c/p\u003e\n\u003cp\u003eThe mean age of these patients was 49.56 ± 13.38 years and the majority was qualified from A/Levels, We have not found statistically significant associations between the detection levels of \u003cem\u003eMethylobacterium\u003c/em\u003e species with periodontal disease status and type 2 diabetes mellitus. However, the small sample size is a limitation of our study. Nevertheless, the implications of our findings could pave the way for future research and highlight the need for further exploration of microbial influences on oral health in Sri Lanka and beyond with powered cohort studies.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements:\u003c/strong\u003e We acknowledge late Professor Newell Johnson, Associate Professor Glen Ulett, Professor of Microbiology, School of Medical Science and Pharmacy, Gold Coast Campus, Griffith University, QLD 4222, Dr. Deepak Ipe and Dr. DJ Speicher for their valuable contribution to make this study success. We extended our gratitude to Prof. WM Tilakaratne, Senior Professor of Oral Pathology, and Prof. L. Samaranayake Professor of Oral Microbiology for their guidance. We thank Oral and Maxillo-Facial Surgeons Dr. Sharika Gunathilake, Dr. S.A.K.J. Kumara, Dr. Ranjith Lal Kandewatte, Dr. P. Kirupakaran, Dr. D.K. Dias, Dr. Chamara Athukorale, Dr. Suresh Shanmuganathan, and Dr. T. Sabesan for facilitating data and sample collection from their respective Oral and Maxillo-Facial Units.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest:\u003c/strong\u003e No potential conflict of interest was reported by the authors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSources of finding:\u003c/strong\u003e This study is funded by Griffith University International Postgraduate Research Scholarship (GUIPRS) 2012, Grant No: MSC 1010,class H,MPP and self-finance (M.P. and I.P.)\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eVaneechoutte M, Dijkshoorn L, Nemec A, K\u0026auml;mpfer P, Wauters G (2011) \u003cem\u003eAcinetobacter\u003c/em\u003e, \u003cem\u003eChryseobacterium\u003c/em\u003e, \u003cem\u003eMoraxella\u003c/em\u003e, and other nonfermentative Gram-negative rods. 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J Clin Microbiol 23:1052\u0026ndash;1055\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBrown MA, Greene JN, Sandin RL, Hiemenz JW, Sinnott JT (1996) \u003cem\u003eMethylobacterium\u003c/em\u003e bacteremia after infusion of contaminated autologous bone marrow. Clin Infect Dis 23:1191\u0026ndash;1192. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://dx.doi.org/10.1093/clinids/23.5.1191\u003c/span\u003e\u003cspan address=\"10.1093/clinids/23.5.1191\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRutherford PC, Narkowicz JE, Wood CJ, Peel MM (1988) Peritonitis caused by \u003cem\u003ePseudomonas mesophilica\u003c/em\u003e in a patient undergoing continuous ambulatory peritoneal dialysis. J Clin Microbiol 26:2441\u0026ndash;2443\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-6945213/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6945213/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjectives:\u003c/strong\u003e The present study aimed to assess the percentage of average relative abundances of \u003cem\u003eMethylobacterium sp. Oral Taxon C7, Methylobacterium sp. Oral Taxon B84, and Methylobacterium hispanicum\u003c/em\u003e and their association with periodontal health and type 2 diabetes in a cohort of Sri Lankan men diagnosed with oral fibroepithelial polyps.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMaterials and methods:\u003c/strong\u003e This retrospective study was based a representative sub-sample of 25 clinically diagnosed oral FEP (the control group) selected from a main case-control study. Amplification of nucle­otides of Extracted DNA from frozen tissues was subjected to nucleotide amplification for the V1 to V3 region. \u0026nbsp;The amplified nucleotides were subjected to sequencing with Illumina’s 2X 300–bp chemistry. The high-quality nonchimeric merged reads were classified to the species level with a prior­itized BLASTN-based algorithm. A structured, pre-tested interviewer administered questionnaire was used to collect socio-demographics, oral risk habits, oral hygiene indicators and \u0026nbsp;medical history data. The data were entered and analyzed using the SPSS 21 Statistical Package. Descriptive statistics were presented as percentage distributions. Fisher’s exact test compared groups with cell counts less than 5.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e The percentage of average relative abundance of \u003cem\u003eMethylobacterium sp\u003c/em\u003e\u003cstrong\u003e. \u003c/strong\u003e\u003cem\u003eOral Taxon C7 was 0.06%, followed by Methylobacterium sp. Oral Taxon B84 was 0.03% and Methylobacterium hispanicum \u003c/em\u003ewas 0.01%. There was no statistically significant association between the percentage of average relative abundance of each \u003cem\u003eMethylobacterium\u003c/em\u003especies with periodontal disease status and T2DM.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eThough\u003cstrong\u003e, \u003c/strong\u003ethere are statistically significance associations this study highlights the need of powered cohort studies to find out possible associations of this nosocomial pathogen with periodontal disease status and T2DM.\u003c/p\u003e","manuscriptTitle":"The percentage of average relative abundances of Methylobacterium sp. Oral Taxon C7, Methylobacterium sp. Oral Taxon B84, and Methylobacterium hispanicumand association with periodontal health and type 2 diabetes in a cohort of Sri Lankan men diagnosed with oral fibroepithelial polyps","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-24 09:30:04","doi":"10.21203/rs.3.rs-6945213/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"36f19879-972c-4ff3-ae27-103c7bc0bcb5","owner":[],"postedDate":"June 24th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-06-24T09:30:04+00:00","versionOfRecord":[],"versionCreatedAt":"2025-06-24 09:30:04","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6945213","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6945213","identity":"rs-6945213","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}