2axc
Crystal structure of ColE7 translocation domain
|
OverviewOverview
ColE7 is a nuclease-type colicin released from Escherichia coli to kill, sensitive bacterial cells by degrading the nucleic acid molecules in their, cytoplasm. ColE7 is classified as one of the group A colicins, since the, N-terminal translocation domain (T-domain) of the nuclease-type colicins, interact with specific membrane-bound or periplasmic Tol proteins during, protein import. Here, we show that if the N-terminal tail of ColE7 is, deleted, ColE7 (residues 63-576) loses its bactericidal activity against, E.coli. Moreover, TolB protein interacts directly with the T-domain of, ColE7 (residues 1-316), but not with the N-terminal deleted T-domain, (residues 60-316), as detected by co-immunoprecipitation experiments, confirming that the N-terminal tail is required for ColE7 interactions, with TolB. The crystal structure of the N-terminal tail deleted ColE7, T-domain was determined by the multi-wavelength anomalous dispersion, method at a resolution of 1.7 angstroms. The structure of the ColE7, T-domain superimposes well with the T-domain of ColE3 and TR-domain of, ColB, a group A Tol-dependent colicin and a group B TonB-dependent, colicin, respectively. The structural resemblance of group A and B, colicins implies that the two groups of colicins may share a mechanistic, connection during cellular import.
About this StructureAbout this Structure
2AXC is a Single protein structure of sequence from Escherichia coli with SO4 and GOL as ligands. Full crystallographic information is available from OCA.
ReferenceReference
High-resolution crystal structure of a truncated ColE7 translocation domain: implications for colicin transport across membranes., Cheng YS, Shi Z, Doudeva LG, Yang WZ, Chak KF, Yuan HS, J Mol Biol. 2006 Feb 10;356(1):22-31. Epub 2005 Dec 5. PMID:16360169
Page seeded by OCA on Wed Nov 21 08:25:57 2007