Draft genome sequence and probiotic functional property analysis of Lactobacillus gasseri LM1065 for food industry applications

Abstract

Probiotics are defined as live organisms in the host that contribute to health benefits. Lactobacillus gasseri LM1065, isolated from human breast milk, was investigated for its probiotic properties based on its genome. Draft genome map and de novo assembly were performed using the PacBio RS II system and hierarchical genome assembly process (HGAP). Probiotic properties were determined by the resistance to gastric conditions, adherence ability, enzyme production, safety assessment and mobile genetic elements. The fungistatic effect and inhibition of hyphae transition were studied using the cell-free supernatant (CFS). L. gasseri LM1065 showed high gastric pepsin tolerance and mild tolerance to bile salts. Auto-aggregation and hydrophobicity were measured to be 61.21% and 61.55%, respectively. The adherence to the human intestinal epithelial cells was measured to be 2.02%. Antibiotic-resistance genes and putative virulence genes were not predicted in the genomic analysis, and antibiotic susceptibility was satisfied by the criteria of the European Food Safety Authority. CFS showed a fungistatic effect and suppressed the tricarboxylic acid cycle in Candida albicans (29.02%). CFS also inhibited the transition to true hyphae and damaged the blastoconidia. This study demonstrates the essential properties of this novel probiotic, L. gasseri LM1065, and potential to inhibit vaginal C. albicans infection.

Lactiplantibacillus plantarum LM1001 Improves Digestibility of Branched-Chain Amino Acids in Whey Proteins and Promotes Myogenesis in C2C12 Myotubes

“…The attachment of Lactobacillus spp. to human enterocytes occurs through the cell surface components of microorganisms such as cell-surface collagen-binding proteins and cell wall-anchored proteins (CWAP; Bae et al, 2023 ). CWAP contains an amino acid motif consisting Leu-Pro-X-Thr-Gly (LPXTG, X: any amino acid), and cleavage of the Thr residue by sortase (Srt) enzymes mediates cell wall attachment to human epithelial cells ( Zhang et al, 2015 ).…”

“…The probiotic properties of L. plantarum LM1001 including its resistance to gastric and bile salt conditions, adhesion to intestinal epithelial cells, and auto-aggregation were measured as described previously ( Bae et al, 2023 ). Briefly, cultured L. plantarum LM1001 was incubated at 37°C either in MRS broth containing pepsin (0.3%, pH 2.5, 2 h) or oxgall (0.3%, 24 h) and the viable cells were counted by spread plate method on MRS agar.…”