Escherichia coli YidC is a membrane insertase for Sec-independent proteins.
YidC is a recently discovered bacterial membrane protein that is related to the mitochondrial Oxa1p and the Alb3 protein of chloroplasts. These proteins are required in the membrane integration process of newly synthesized proteins that do not require the classical Sec machinery. Here we demonstrate that YidC is sufficient for the membrane integration of a Sec-independent protein. Microgram amounts of the purified single-spanning Pf3 coat protein were efficiently inserted into proteoliposomes containing the purified YidC. A mutant Pf3 coat protein with an extended hydrophobic region was inserted independently of YidC into the membrane both in vivo and in vitro, but its insertion was accelerated by YidC. These results show that YidC can function separately from the Sec translocase to integrate membrane proteins into the lipid bilayer.
Serek
Justyna
J
Institute of Microbiology and Molecular Biology, University of Hohenheim, Stuttgart, Germany.
Bauer-Manz
Gabriele
G
Struhalla
Gabriele
G
van den Berg
Lambertus
L
Kiefer
Dorothee
D
Dalbey
Ross
R
Kuhn
Andreas
A
D000251:Adenosine Triphosphatases / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism; D036022:Capsid Proteins / Q000737:chemistry / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000502:physiology*; D008081:Liposomes / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000378:metabolism / Q000502:physiology*; D011510:Proteolipids / Q000378:metabolism; D000069816:SEC Translocation Channels; D000081416:SecA Proteins
D001426:Bacterial Proteins; D036022:Capsid Proteins; D029968:Escherichia coli Proteins; D008081:Liposomes; D026901:Membrane Transport Proteins; D011510:Proteolipids; D000069816:SEC Translocation Channels; C412443:YIDC protein, E coli; C020485:proteoliposomes; C084332:major coat protein, Pseudomonas phage Pf3; D000251:Adenosine Triphosphatases; D000081416:SecA Proteins