Lactosporin, a natural antimicrobial protein for control of bacterial vaginosis

Bacterial vaginosis (BV) is one the most common infections in women of reproductive age which results from the replacement of healthy vaginal microflora mostly by anaerobic pathogens such as Gardnerella vaginalis, Prevotella bivia and Peptostreptococcus spp. Conventional treatment of BV with the antibiotics metronidazole and clindamycin, as recommended by the Centers for Disease Control and Prevention, does not eradicate all of the microorganisms associated with BV and many women remain colonized with G. vaginalis and other anaerobes and inhibit the healthy vaginal microflora such as Lactobacillus spp. Lactosporin, a natural antimicrobial protein produced by Bacillus coagulans ATCC 7050 have shown to be an effective and safe alternative for BV treatment. This dissertation describes the isolation, characterization, mode of action and safety of lactosporin. Lactosporin was found to be an anionic (pI=3.5-4), heat stable protein that its activity is highly pH dependent. Lactosporin inhibited G. vaginalis in well diffusion assay while it had no effect on healthy vaginal lactobacilli. Mode of action studies established that lactosporin inhibits G. vaginalis by forming pores in the cytoplasmic membrane, causing efflux of intracellular material and dissipation of the ΔpH component of the proton motive force (PMF). The saferty of lactosporin was evaluated in-vitro by using EpiVaginal[trade mark] ectocervical tissue model where it was shown to be a safe, non-toxic preparation for feminine care application.Ph. D.Includes bibliographical referencesIncludes vitaby Shadi Riaz