Overexpression of phosphatidylglycerophosphate synthase restores protein translocation in a secG deletion mutant of Escherichia coli at low temperature.
The E. coli secG deletion mutant is unable to grow and is defective in protein translocation at low temperature. A gene of Bacillus subtilis, which is able to restore the growth of the deletion mutant at low temperature, was found as a multi-copy suppressor. Sequencing of this gene revealed significant homology to E. coli pgsA, which encodes phosphatidylglycerophosphate synthase, an enzyme involved in acidic phospholipid synthesis. A plasmid carrying E. coli pgsA also restored the growth of the deletion mutant. Furthermore, protein translocation in the deletion mutant was stimulated when it harbored a plasmid carrying pgsA. A possible mechanism underlying the pgsA-dependent suppression of the secG deletion mutation is discussed.
Kontinen
V P
VP
Institute of Molecular and Cellular Biosciences, University of Tokyo, Japan.
Tokuda
H
H
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism*; D001483:Base Sequence; D001693:Biological Transport, Active; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D029968:Escherichia coli Proteins; D017353:Gene Deletion; D015870:Gene Expression; D005798:Genes, Bacterial; D008565:Membrane Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D000069816:SEC Translocation Channels; D017386:Sequence Homology, Amino Acid; D013489:Suppression, Genetic; D013696:Temperature; D017855:Transferases (Other Substituted Phosphate Groups) / Q000235:genetics*
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D000069816:SEC Translocation Channels; C088616:SecG protein, E coli; D017855:Transferases (Other Substituted Phosphate Groups); C020676:CDP-diacylglycerol-glycerol-3-phosphate 3-phosphatidyltransferase