Variable stoichiometry of the TatA component of the twin-arginine protein transport system observed by in vivo single-molecule imaging.

ABSTRACT: The twin-arginine translocation (Tat) system transports folded proteins across the bacterial cytoplasmic membrane and the thylakoid membrane of plant chloroplasts. The essential components of the Tat pathway are the membrane proteins TatA, TatB, and TatC. TatA is thought to form the protein translocating element of the Tat system. Current models for Tat transport make predictions about the oligomeric state of TatA and whether, and how, this state changes during the transport cycle. We determined the oligomeric state of TatA directly at native levels of expression in living cells by photophysical analysis of individual yellow fluorescent protein-labeled TatA complexes. TatA forms complexes exhibiting a broad range of stoichiometries with an average of approximately 25 TatA subunits per comp

SUBMITTER: Leake MC 

PROVIDER: S-EPMC2563114 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature