Molecular characterization of the oligopeptide permease of Salmonella typhimurium

摘要: The oligopeptide permease (Opp) of Salmonella typhimurium is a periplasmic binding protein-dependent transport system and handles any peptides containing from two to five amino acid residues. Opp plays an important nutritional role also required for the recycling cell wall peptides. We have determined nucleotide sequence opp operon. In addition four genes identified previously by genetic means (oppABCD) fifth gene, oppF, shown be cotranscribed as part Using reverse genetics, we show that oppF encodes essential component system. proteins, OppABCDF, are only proteins function. Regulation expression differential within operon investigated. devised simple constructing lacZ gene fusions S. chromosomal in vivo, using derivatives bacteriophage Mu. this procedure, opp-lacZ were selected. resultant Opp-LacZ hybrid used OppB, OppC OppD membrane-associated proteins. A detailed comparison components with those other systems provides insight into mechanisms evolution these systems.