Structure of a translocation signal domain mediating conjugative transfer by type IV secretion systems.

ABSTRACT: Relaxases are proteins responsible for the transfer of plasmid and chromosomal DNA from one bacterium to another during conjugation. They covalently react with a specific phosphodiester bond within DNA origin of transfer sequences, forming a nucleo-protein complex which is subsequently recruited for transport by a plasmid-encoded type IV secretion system. In previous work we identified the targeting translocation signals presented by the conjugative relaxase TraI of plasmid R1. Here we report the structure of TraI translocation signal TSA. In contrast to known translocation signals we show that TSA is an independent folding unit and thus forms a bona fide structural domain. This domain can be further divided into three subdomains with striking structural homology with helicase subdomains o

SUBMITTER: Redzej A 

PROVIDER: S-EPMC3912908 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature