Biogenesis of inner membrane proteins in Escherichia coli.
Gram-negative bacteria such as Escherichia coli are surrounded by two membranes, the inner membrane and the outer membrane. The biogenesis of most inner membrane proteins (IMPs), typical alpha-helical proteins, appears to follow a partly conserved cotranslational pathway. Targeting involves a relatively simple signal recognition particle (SRP) and SRP-receptor. Insertion of most IMPs into the membrane occurs via the Sec-translocon, which is also used for the vectorial transport of secretory proteins. Similar to eukaryotic systems, little is known about the later stages of biogenesis of IMPs, the folding and assembly in the lipid bilayer. Recently, YidC has been identified as a factor that assists in the integration, folding, and assembly of IMPs both in association with the Sec-translocon and separately. This review deals mainly with recent structural and biochemical data from various experimental systems that offer new insight into the different stages of biogenesis of E. coli IMPs.
Luirink
Joen
J
Department of Microbiology, Institute of Molecular Cell Biology, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands. joen.luirink@falw.vu.nl
von Heijne
Gunnar
G
Houben
Edith
E
de Gier
Jan-Willem
JW
D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D018271:Signal Recognition Particle / Q000378:metabolism
D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D018271:Signal Recognition Particle