Probiotic Characteristics and Whole-Genome Profiling of Lactiplantibacillus plantarum V2 Isolated from Tibetan Plateau Traditional Yogurt

Abstract

Lactiplantibacillus plantarum V2 is a probiotic strain isolated from yogurt by Tibetan Plateau herdsmen in China. In this study, we systematically evaluated the probiotic potential and genome-wide features of L. plantarum V2. The cell-free supernatants (CFSs) of strain V2 exhibited broad-spectrum antimicrobial activity against at least 13 species of pathogenic bacteria. Moreover, L. plantarum V2 showed excellent gastrointestinal tract adaptability: it maintained a survival rate of 83.02 ± 1.64% at pH 3.0 an retained a survival rate of 20.34 ± 0.48% after 24 h exposure to 0.3% bile salts. Strain V2 adhered to Caco-2 cells with an efficiency of 1.83 ± 0.54%. It displayed non-hemolytic activity, was susceptible to clinically relevant broad-spectrum antibiotics, and harbored no transferable antimicrobial resistance genes. Whole-genome sequencing (WGS) analysis revealed that strain V2 possesses one circular chromosome and one linear plasmid, which collectively encode 3,041 coding sequences (CDSs), 16 rRNA genes, 71 tRNA genes, 12 CRISPR arrays, and a complete prophage region. Key functional genetic elements of strain V2 include five gene clusters encoding broad-spectrum antimicrobial peptides, six regions associated with environmental adaptability, 129 carbohydrate-active enzyme (CAZyme) genes, and one specialized metabolic cluster. Functional annotation further highlighted enriched pathways involved in transcriptional regulation, as well as the transport and metabolism of carbohydrates and amino acids. Collectively, our in vitro data demonstrate that L. plantarum V2 exhibits favorable acid and bile tolerance, potent bacteriostatic activity, and genomic safety, making it a promising candidate for applications in the livestock breeding and feed industries.