Abstract
The increasing demand for tasty dairy products has raised the interest for strains of lactic acid bacteria with novel properties. In this study we have explored the proteolytic system of 24 wild Lactococcus lactis strains isolated previously from Spanish raw milk cheeses, to select proteolytic strains with high peptidase activity and efficient peptide transport capability. Large variations in overall proteolysis, proteolytic activities, as well as in peptide utilization, were recorded among strains. Peptide utilization correlated well with the presence of oligopeptide transport systems (Opp and Dpp) in wild L. lactis strains. Eighteen of the 24 wild L. lactis strains possessed both Opp and Dpp systems, what supports the theory that the presence of both oligopeptide transport systems could confer an advantage to the strain. Differences in the nucleotide sequence of genes coding for the oligopeptide binding proteins were shown by means of restriction endonuclease analyses. Based on the characteristics determined in this work, L. lactis strains ESI197, M21 and P21 seem to be promising candidates for use as components of starter cultures.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.