Mode of action and safety of lactosporin, a novel antimicrobial protein produced by Bacillus coagulans ATCC 7050

Abstract

Aims To determine the mechanism of action of antimicrobial protein, lactosporin, against Gardnerella vaginalis and to evaluate its safety in vitro. Methods and Results Bacillus coagulans ATCC 7050 was grown at 37°C for 18 h. The cell‐free supernatant was concentrated 10‐fold and screened for antimicrobial activity against indicator strain Micrococcus luteus. The mode of action of lactosporin was determined by measuring the potassium release and monitoring the changes in transmembrane potential (Δψ) and transmembrane pH (ΔpH) of the sensitive cells. Lactosporin caused the efflux of potassium ions from M. luteus cells and dissipation of ΔpH in G. vaginalis, while it had no effect on the Δψ. The safety of lactosporin was evaluated by using EpiVaginal™ ectocervical (VEC‐100) tissue model. Over 80% of the cells in the vaginal tissue remained viable after exposure to lactosporin for 24 h. Conclusions Lactosporin potentially exerts its antimicrobial activity by selective dissipation of ΔpH and/or by causing leakage of ions from the sensitive cells. Safety studies suggest that lactosporin is a noncytotoxic antimicrobial for vaginal application. Significance and Impact of the Study This study revealed that lactosporin is an effective and safe antimicrobial preparation with potential application for the control of bacterial vaginosis.

Isolation and Characterization of a Bacteriocin-Like Substance Produced by Geobacillus toebii Strain HBB-247

“…2). Similar results have been reported for other bacteriocins with high ([10 kDa) molecular weight, thermoleovorins [7], thermophilin ST-1 [18], nigrecin [21], cerein 8A [22], lactosporin [23].…”

Bacteriocinogenic potential of a probiotic strain Bacillus coagulans [BDU3] from Ngari

“…Subtilosin A is a ribosomally synthesized and post-translationally modified antimicrobial peptide produced by B. subtilis and active against a variety of Gram-positive bacteria including the foodborne pathogen L. monocytogenes [14]. Riazi et al (2009) [15] reported lactosporin production from Bacillus coagulans isolated from a probiotic dietary supplement, Lactospore ® probiotic.…”

Molecular Characterization and In Vitro Analyses of a Sporogenous Bacterium with Potential Probiotic Properties

“…This specific and limited spectrum of inhibition may be due to the synthesis of bacteriocin-like inhibitory substances (BLIS). Bacillus coagulans has been reported to produce coagulin and lactosporin as BLIS (23,35).…”

“…Studies pertaining to the effects of proprietary B. coagulans such as GanedenBC30 TM preparation as a food ingredient on symptoms of diarrhea-predominant irritable bowel syndrome and assessment of safety of such kind of preparations have also been demonstrated in literature [10][11][12]. Bacillus coagulans preparations have been reported to produce bacteriocin-like inhibitory substances (BLIS) e.g., coagulin and lactosporin [23,35].…”