L-Alanine Exporter AlaE Functions as One of the d-Alanine Exporters in Escherichia coli.

ABSTRACT: d-amino acids have recently been found to be present in the extracellular milieu at millimolar levels and are therefore assumed to play a physiological function. However, the pathway (or potential pathways) by which these d-amino acids are secreted remains unknown. Recently, Escherichia coli has been found to possess one or more energy-dependent d-alanine export systems. To gain insight into these systems, we developed a novel screening system in which cells expressing a putative d-alanine exporter could support the growth of d-alanine auxotrophs in the presence of l-alanyl-l-alanine. In the initial screening, five d-alanine exporter candidates, AlaE, YmcD, YciC, YraM, and YidH, were identified. Transport assays of radiolabeled d-alanine in cells expressing these candidates indicate

SUBMITTER: Katsube S 

PROVIDER: S-EPMC10299036 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature