Comparative genomics and characterization of highly adhesive and stress resistant Lacticaseibacillus paracasei strain...

Lacticaseibacillus paracasei strains have a long history of safe use in food products, particularly fermented foods such as yogurt and cheese. These strains are known for their health-promoting probiotic attributes. Recently, we de novo assembled the whole genome of Lacticaseibacillus paracasei subsp. paracasei strain E, originally isolated from cheese and later studied as an adjunct starter in cheesemaking. In this study, the strain's probiotic properties and their potential genetic basis were analyzed using the combination of in vitro and in silico methods. This analysis particularly focused on correlating specific phenotypic traits with the presence or absence of specific gene sets. The strain E harbours two copies of the same spaCBA-srtC1 pilus gene cluster as L. rhamnosus GG, and it expresses more SpaC pilins, even though the overall adhesion to mucus was found to be somewhat lower than that of LGG. The strain E exhibited better tolerance to simulated gastrointestinal condition and remarkably higher cell surface hydrophobicity than LGG, suggesting distinct surface properties and hence a different preference for binding to host cells. Taken together, these findings indicate that L. paracasei E has potential as a probiotic strain.