The oligopeptide transport system is essential for the development of natural competence in Streptococcus thermophilus strain LMD-9.

ABSTRACT: In gram-positive bacteria, oligopeptide transport systems, called Opp or Ami, play a role in nutrition but are also involved in the internalization of signaling peptides that take part in the functioning of quorum-sensing pathways. Our objective was to reveal functions that are controlled by Ami via quorum-sensing mechanisms in Streptococcus thermophilus, a nonpathogenic bacterium widely used in dairy technology in association with other bacteria. Using a label-free proteomic approach combining one-dimensional electrophoresis with liquid chromatography-tandem mass spectrometry analysis, we compared the proteome of the S. thermophilus LMD-9 to that of a mutant deleted for the subunits C, D, and E of the ami operon. Both strains were grown in a chemically defined medium (CDM) without peptide

SUBMITTER: Gardan R 

PROVIDER: S-EPMC2704715 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature