Elevated cytosolic concentrations of SecA compensate for a protein translocation defect in Escherichia coli cells with reduced levels of negatively charged phospholipids
- 10 August 1992
- journal article
- Published by Wiley in FEBS Letters
- Vol. 308 (1) , 97-100
- https://doi.org/10.1016/0014-5793(92)81060-y
Abstract
Cellular extracts from cells with reduced synthesis of negatively charged phospholipids were found to support in vitro translocation of the precursor of the outer membrane protein PhoE with increased efficiency. Analysis of these extracts revealed that they contain increased levels of SecA. SecA depletion resulted in a loss of the translocation stimulatory activity, which could be restored by re-addition of purified SecA. We conclude that elevated cytosolic levels of SecA counteract the reduction of translocation efficiency due to low levels of negatively charged phospholipids in the inner membrane.Keywords
This publication has 22 references indexed in Scilit:
- SecA insertion into phospholipids is stimulated by negatively charged lipids and inhibited by ATP: a monolayer studyBiochemistry, 1992
- Conservation of components of the export machinery in prokaryotesFEMS Microbiology Letters, 1991
- ΔμH+ and ATP function at different steps of the catalytic cycle of preprotein translocaseCell, 1991
- The binding cascade of SecB to SecA to SecYE mediates preprotein targeting to the E. coli plasma membraneCell, 1990
- The ATPase activity of secA is regulated by acidic phospholipids, secY, and the leader and mature domains of precursor proteinsCell, 1990
- Phosphatidylglycerol is involved in protein translocation across Escherichia coli inner membranesNature, 1988
- Optimal posttranslational translocation of the precursor of PhoE protein across Escherichia coli membrane vesicles requires both ATP and the protonmotive forceBiochimica et Biophysica Acta (BBA) - Biomembranes, 1987
- Regulation of a membrane component required for protein secretion in escherichia coliCell, 1982
- The sedimentation behaviour of ribonuclease-active and -inactive ribosomes from bacteriaBiochemical Journal, 1965