Abstract
Lactiplantibacillus plantarum MS11, isolated from traditionally fermented yak milk in the high-altitude Gannan region of the eastern Tibetan Plateau, was investigated for its technological and functional potential in food applications. Using whole-genome sequencing combined with targeted experimental verification, this study clarified the genetic determinants and metabolic capacity associated with its production of folate, lactic acid, bacteriocin, and exopolysaccharides (EPS). The MS11 genome consists of one circular chromosome and three plasmids, totaling 3,318,231 bp with a GC content of 44.48%, and encodes 3155 predicted open reading frames. Complete biosynthetic gene clusters were identified for folate (7 genes), L-lactic acid (13 genes), bacteriocin (14 genes), and EPS (17 genes). Phenotypic assays confirmed the strain’s high metabolite productivity, including folate (0.6043 μg/mL), L-lactic acid (76.24 mg/mL), and EPS (544.2 mg/L). The cell-free fermented supernatant exhibited strong antibacterial activity against Escherichia coli, supporting the functional relevance of its bacteriocin-associated gene cluster. To the best of our knowledge, this is the integrated genomic and experimental characterization demonstrating that a L. plantarum strain originating from a unique high-altitude fermented dairy niche can concurrently synthesize high levels of folate together with multiple beneficial metabolites. The multifunctional attributes of MS11—including nutrient fortification, acidification capacity, EPS formation, and antimicrobial activity—indicate substantial promise for its application as a composite starter culture, natural bio-preservative, and nutritionally enhanced probiotic in fermented food systems.