HEALTH NEWS

Study Title:

Friendly Flora Disrupts Infectious E. Coli Biofilms

Study Abstract

The process that changes a relatively sparse vaginal microbiota of healthy women into a dense biofilm of pathogenic and potentially pathogenic bacteria is poorly understood. Likewise, the reverse step whereby an aberrant biofilm is displaced and returns to a healthy lactobacilli dominated microbiota is unclear. In order to study these phenomena, in vitro experiments were performed to examine the structure of biofilms associated with aerobic vaginosis, urinary tract infections, and bacterial vaginosis (BV). Uropathogenic Escherichia coli were able to form relatively thin biofilms within five days (6μm height), while Atopobium vaginae and Gardnerella vaginalis formed thicker biofilms 12μm in height within two days. Challenge of E. coli biofilms with lactobacilli did not result in pathogen displacement. However, the resulting thicker lactobacilli infused biofilms, caused significant E. coli killing. E. coli biofilms challenged with secreted products of L. rhamnosus GR-1 caused a marked decrease in cell density, and increased cell death. Similarly challenge of BV biofilms with lactobacilli infiltrated BV biofilms and caused bacterial cell death. Metronidazole produced holes in the biofilm but did not eradicate the organisms. The findings provide some evidence of how lactobacilli probiotics might interfere with an aberrant vaginal microbiota, and strengthen the position that combining probiotics with antimicrobials could better eradicate pathogenic biofilms.

Study Information

McMillan A, Dell M, Zellar MP, Cribby S, Martz S, Hong E, Fu J, Abbas A, Dang T, Miller W, Reid G.
Disruption of urogenital biofilms by lactobacilli.
Colloids Surf B Biointerfaces.
2011 August
Human Microbiology and Probiotics, Lawson Health Research Institute, 268 Grosvenor Street, London, Ontario N6A 4V2, Canada.