In Silico and In Vitro Characterization of Bacillus velezensis P45: Screening for a Novel Probiotic Candidate

Area of Science:

• Microbiology
• Probiotics
• Food Science

Background:

• Spore-forming Bacilli are explored for biotechnological applications and functional foods.
• Probiotics offer potential benefits for human health and disease prevention.

Purpose of the Study:

• To genetically and phenotypically characterize the probiotic properties of Bacillus velezensis P45.
• To evaluate the safety and functional capabilities of B. velezensis P45 for potential probiotic use.

Main Methods:

• In vitro assessment of antimicrobial activity, autoaggregation, and biofilm formation.
• Gastrointestinal tolerance, mucin adhesion, and in silico safety analysis (virulence factors, antibiotic resistance).
• Genome mining for adhesion and secondary metabolite synthesis genes; phylogenetic analysis using the yloA (rqcH) gene.

Main Results:

• B. velezensis P45 demonstrated antimicrobial activity against pathogens and strong autoaggregation and biofilm formation.
• The strain exhibited tolerance to gastrointestinal conditions and mucin adhesion capabilities.
• In silico analysis confirmed safety; genome mining identified adhesion and antimicrobial lipopeptide genes (fengycin, surfactin, bacillibactin). Phylogenetic analysis supported its probiotic potential.

Conclusions:

• Bacillus velezensis P45 possesses significant functional probiotic properties, including antimicrobial activity and adherence.
• The strain is deemed safe due to the absence of virulence factors and antibiotic resistance genes.
• B. velezensis P45 is a promising candidate for probiotic applications in functional foods and human health.