Genomic Insights into Probiotic Lactococcus lactis T-21, a Wild Plant-Associated Lactic Acid Bacterium, and Its Preliminary Clinical Investigation for Human Application. Lactococcus lactis subsp. lactis strain:T-21

This investigation elucidates a thorough genomic characterization of Lactococcus lactis T-21, a wild, plant-associated lactic acid bacterium, and evaluates its safety through initial clinical trials. Isolated from wild cranberries in Japan, T-21 demonstrates significant immunomodulatory properties and has been incorporated into commercial health products. Employing in-depth genomic analysis and comparison with both wild and domesticated dairy strains, this study illuminates the genetic diversity and distinct metabolic capabilities of T-21, accentuating its substantial capacity for exopolysaccharide production and nisin biosynthesis. These attributes, indicative of its wild plant origin, potentially underpin its unique probiotic functionalities. A preliminary clinical trial assessing the safety of T-21 fermented milk in healthy Japanese adults indicated no significant adverse outcomes, corroborating its safety for human consumption. The findings, including the genomic insights, endorse the feasibility of utilizing non-dairy, wild plant-origin strains in dairy fermentation processes as probiotics. This research not only expands our comprehension of the genomic basis for T-21's probiotic potential but also lays the groundwork for further exploration of its applications in promoting human health.