Electrochemical potential releases a membrane-bound secretion intermediate of maltose-binding protein in Escherichia coli.
AUTOR(ES)
Geller, B L
RESUMO
A secretionary intermediate of the Escherichia coli maltose-binding protein accumulated in the inner membrane when the membrane electrochemical potential was reduced and the cytosolic ATP concentration was normal. The intermediate was mature in size, but maintained a conformation similar to the cytosolic precursor form, and not the mature periplasmic protein, as measured by differences in susceptibility to proteinase K in vitro. The intermediate was located on the periplasmic side of the inner membrane. Restoration of the membrane electrochemical potential resulted in the movement of the intermediate from the inner membrane to the periplasm. In other experiments in which the ATP concentration was reduced by 96% and the electrochemical potential remained normal, no intermediate accumulated. Thus, the final step in the export of maltose-binding protein requires the electrochemical potential of the inner membrane and does not require ATP.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=213141Documentos Relacionados
- Interaction of the maltose-binding protein with membrane vesicles of Escherichia coli.
- Periplasmic maltose-binding protein confers specificity on the outer membrane maltose pore of Escherichia coli.
- Two regions of mature periplasmic maltose-binding protein of Escherichia coli involved in secretion.
- Mutations that improve export of maltose-binding protein in SecB- cells of Escherichia coli.
- Active transport of maltose in membrane vesicles obtained from Escherichia coli cells producing tethered maltose-binding protein.