Differential vaginalLactobacillusspecies metabolism of glucose, L and D-lactate by13C-nuclear magnetic resonance spectroscopy

Introduction Cervicovaginal dysbiosis can lead to infection-associated spontaneous preterm birth. Objective To determine whether vaginal Lactobacillus species, L. crispatus and L. jensenii , differentially metabolise glucose, L- and/or D-lactate to propagate their survival/dominance. Methods Bacteria were incubated anaerobically for 24h at 37°C, with 13 C u -glucose, 13 C 3 -D-lactate or 13 C 3 -L-lactate (singularly or combined) for 24h. 13 C-spectra were acquired using a 9.4T NMR spectrometer. Results L. crispatus and L. jensenii (n=6 each) metabolised 13 C-glucose to 13 C-lactate and 13 C-acetate. L. jensenii converted more 13 C 3 -D- or 13 C 3 -L-lactate to 13 C-acetate than L. crispatus , p<0.001. Conclusion Conversion of glucose and lactate to acetate by L. jensenii compared to L. crispatus , suggests a possibly important pathomechanism of dysbiosis and infection-associated spontaneous preterm birth.