作者: E J Smid , R Plapp , W N Konings
DOI: 10.1128/JB.171.11.6135-6140.1989
关键词: Casein 、 Lactococcus lactis 、 Peptide transport 、 Wild type 、 Dipeptide 、 Tripeptide transport 、 Oligopeptide transport 、 Biology 、 Biochemistry 、 Tripeptide
摘要: The chlorated dipeptide L-alanyl-beta-chloro-L-alanine (diACA) is very toxic for Lactococcus lactis. Spontaneous mutants resistant to the were isolated from plates. presence and activities of cell wall-associated proteinase, different peptidases in extracts, amino acid transport systems, di- oligopeptide systems examined compared a diACA-resistant mutant wild type. Only rates tripeptide found be significantly reduced L. lactis ML3. Since all other characteristics this comparable those type, most likely deficient transport. Uptake tripeptides by ML3 was mainly mediated one peptide system. transport-deficient unable grow on chemically defined medium supplemented with casein as sole nitrogen source, whereas growth could restored addition acids. These results indicate that an essential component process utilization during milk. Images