An anionic peptide transport system in Streptococcus faecalis

Characterization of two peptide-transport systems in Streptococcus faecalis.

Streptococcus faecalis proton gradients and tetracycline transport.

The transport of chlortetracycline by Streptococcus faecalis is energy dependent. Addition of glucose to energy-depleted cells enhances both the transport rates and accumulation levels. Transport rates can be altered independently of glucose by treating cells with ionophores that increase or decrease the proton gradient. The transport of the antibiotic is linked only to the transmembrane pH dif...

Transport of aminophosphonic acids in Lactobacillus plantarum and Streptococcus faecalis.

Aminophosphonic acids analogous to glutamic acid, aspartic acid, alanine, and valine were actively accumulated by Lactobacillus plantarum. Uptake was dependent on the availability of glucose and, in all cases, the estimated intracellular concentrations substantially exceeded extracellular levels. During uptake, there was little metabolism of tritiated 2-amino-3-phosphonopropionic acid (APP), th...

Hydroxylysine metabolism in Streptococcus faecalis.

The characteristics of peptide uptake in Streptococcus faecalis: studies on the transport of natural peptides and antibacterial phosphonopeptides.

Transport of natural peptides and antibacterial phosphonopeptide analogues was studied in Streptococcus faecalis ATCC 9790. Competition studies, and the isolation of peptide-transport deficient mutants, indicate the presence of two peptide permeases. One is a high-rate system used by dipeptides, and to a lesser extent tripeptides; the other is a low-rate oligopeptide system. Following uptake, p...