Trigger factor depletion or overproduction causes defective cell division but does not block protein export.
Trigger factor is an abundant cytosolic protein of Escherichia coli which can stabilize proOmpA for in vitro translocation across inner membrane vesicles. The gene encoding E. coli trigger factor was isolated and sequenced, allowing construction of strains in which the expression of trigger factor is readily regulated. We found no defect in the in vivo rate of synthesis or secretion of proOmpA in trigger factor-depleted cells. The primary physiological defect in trigger factor-depleted or -overproducing cells is an enrichment of filamented cells. Filamentation of the trigger factor-overproducing strain is suppressed by a multicopy plasmid expressing the essential division gene ftsZ, suggesting that trigger factor has an important role in cell division.
Guthrie
B
B
Molecular Biology Institute, University of California, Los Angeles 90024-1737.
Wickner
W
W
D000591:Amino Acid Isomerases / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism; D002455:Cell Division; D002872:Chromosome Deletion; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000166:cytology / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins; D015723:Gene Library; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D009154:Mutation; D015345:Oligonucleotide Probes; D019696:Peptidylprolyl Isomerase; D011498:Protein Precursors / Q000378:metabolism; D015183:Restriction Mapping
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; D015345:Oligonucleotide Probes; D011498:Protein Precursors; C057184:outer membrane protein A precursor (E coli); D000591:Amino Acid Isomerases; D019696:Peptidylprolyl Isomerase