Safety assessment of five candidate probiotic lactobacilli using comparative genome analysis

Area of Science:

• Microbiology
• Genomics
• Probiotic Safety

Background:

• Lactobacillus genus complex probiotics are generally safe but can be pathogenic.
• Understanding genetic factors is crucial for assessing probiotic safety.
• Specific probiotic strains like Limosilactobacillus mucosae LM1 and Lactiplantibacillus plantarum SK151 require safety evaluation.

Purpose of the Study:

• To identify potential virulence factors and antibiotic resistance (AR) genes in selected probiotic strains.
• To assess the safety profiles of Limosilactobacillus mucosae LM1, Lactiplantibacillus plantarum SK151, Lactiplantibacillus plantarum BS25, Limosilactobacillus fermentum SK152, and Lactobacillus johnsonii PF01.
• To contribute to pre-clinical safety assessment strategies for probiotics.

Main Methods:

• Genome sequencing for L. plantarum BS25 and annotation using Rapid Annotation using Subsystem Technology (RAST).
• Bioinformatic analysis using command-line BLAST against the Virulence Factor Database (VFDB) and Comprehensive Antibiotic Resistance Database (CARD).
• Detection of acquired AR genes using ResFinder.

Main Results:

• Genes associated with bacterial survival, platelet aggregation, surface adhesion, biofilm formation, and immunoregulation were identified.
• No acquired antibiotic resistance genes were detected using CARD and ResFinder.
• The analyzed probiotic strains possess genes homologous to those found in pathogenic bacteria, primarily related to survival and adherence.

Conclusions:

• The study provides insights into the genetic basis of potential pathogenicity in probiotics.
• Whole-genome data analysis is a valuable tool for pre-clinical probiotic safety assessments.
• Gene mining combined with experimental validation can enhance future probiotic safety strategies.