Trigger factor retards protein export in Escherichia coli.

摘要: Trigger factor (TF) is a ribosome-associated protein that interacts with wide variety of nascent polypeptides in Escherichia coli. Previous studies have indicated TF cooperates DnaK to facilitate folding, but the basis this cooperation unclear. In study we monitored export E. coli lack or overproduce obtain further insights into its function. Whereas inactivation genes encoding most molecular chaperones (including dnaK) impairs export, gene accelerated and suppressed need for targeting factors maintain translocation competence presecretory proteins. Furthermore, overproduction (but not DnaK) markedly retarded export. Manipulation levels produced similar effects on cytosolic enzyme fused signal peptide. The data strongly suggest has unique ability sequester relatively prolonged period. Based our results, propose promote folding by distinct complementary) mechanisms.