Trigger factor is a bona fide secretory pathway chaperone that interacts with SecB and the translocase

ABSTRACT: Bacterial secretory preproteins are translocated across the inner membrane post-translationally by the SecYEG-SecA translocase. Mature domain features and signal peptides maintain preproteins in kinetically trapped, largely soluble, folding intermediates. Some aggregation prone preproteins require chaperones, like trigger factor (TF) and SecB, for solubility and/or targeting. TF antagonizes the contribution of SecB to secretion by an unknown molecular mechanism. We reconstituted this interaction in vitro and studied targeting and secretion of the model preprotein proOmpA. TF and SecB display distinct, unsuspected roles in secretion. Tightly associating TF:proOmpA target the translocase at SecA, but TF prevents proOmpA secretion. In solution, SecB binds TF:proOmpA with high affinity. At the

SUBMITTER: Ms Jozefien De Geyter 

PROVIDER: S-SCDT-EMBOR-2019-49054V1 | biostudies-other |

REPOSITORIES: biostudies-other