Article

Purification, crystallization and preliminary structural characterization of the periplasmic domain P1 of the Escherichia coli membrane-protein insertase YidC.

Biochemie-Zentrum der Universität Heidelberg (BZH), INF 328, D-69120 Heidelberg, Germany.
Acta Crystallographica Section F Structural Biology and Crystallization Communications (impact factor: 0.51). 03/2008; 64(Pt 2):144-8. DOI:10.1107/S1744309108002364
Source: PubMed

ABSTRACT In Escherichia coli, the biogenesis of inner membrane proteins (IMPs) requires targeting and insertion factors such as the signal recognition particle (SRP) and the Sec translocon. Recent studies have identified YidC as a novel and essential component involved in membrane insertion of IMPs both in conjunction with the Sec translocon and as a separate entity. E. coli YidC is a member of the YidC (in bacteria)/Oxa1 (in mitochondria)/Alb3 (in chloroplasts) protein family and contains six transmembrane segments and a very large periplasmic domain P1. The overproduction, purification, crystallization and preliminary crystallographic studies of the native and selenomethionine-labelled P1 domain are reported here as a first step towards the elucidation of the molecular mechanism of YidC as a membrane-protein insertase.

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Keywords

elucidation
 
Escherichia coli
 
essential component
 
first step
 
insertion factors
 
large periplasmic domain P1
 
membrane insertion
 
mitochondria)/Alb3
 
molecular mechanism
 
native
 
purification
 
Recent studies
 
Sec translocon
 
separate entity
 
signal recognition particle
 
transmembrane segments