Lactobacillus crispatus (L. crispatus)

Lactobacillus crispatus is a Gram-positive, anaerobic, rod-shaped bacterium that is a dominant and defining member of the healthy human vaginal microbiota (Petrova et al., 2015). It plays a critical role in maintaining urogenital health by producing high levels of L-lactic acid, which maintains a low vaginal pH (typically <4.5) to inhibit the growth of dysbiotic bacteria such as Gardnerella vaginalis (O'Hanlon et al., 2013). In addition to acidification, L. crispatus produces hydrogen peroxide and antimicrobial peptides like bacteriocins, which provide a protective barrier against sexually transmitted infections, including HIV and HSV-2 (Valenti et al., 2018). While not a traditional molecular target like a receptor or enzyme, L. crispatus is the primary component of emerging live biotherapeutic products (LBPs) such as LACTIN-V, which is used to restore the vaginal microbiome and prevent the recurrence of bacterial vaginosis (Cohen et al., 2020). Its presence is also used as a clinical biomarker for a stable vaginal environment and is associated with a reduced risk of preterm birth and pelvic inflammatory disease (Petrova et al., 2015).

Other names

L. crispatusLactobacillus acidophilus group (historical)

Competitive exclusion and environmental acidification through the production of L-lactic acid and hydrogen peroxide (O'Hanlon et al., 2013; Valenti et al., 2018).