The Colicin E1 TolC Box: Identification of a Domain Required for Colicin E1 Cytotoxicity and TolC Binding.

ABSTRACT: Colicins are protein toxins made by Escherichia coli to kill related bacteria that compete for scarce resources. All colicins must cross the target cell outer membrane in order to reach their intracellular targets. Normally, the first step in the intoxication process is the tight binding of the colicin to an outer membrane receptor protein via its central receptor-binding domain. It is shown here that for one colicin, E1, that step, although it greatly increases the efficiency of killing, is not absolutely necessary. For colicin E1, the second step, translocation, relies on the outer membrane/transperiplasmic protein TolC. The normal role of TolC in bacteria is as an essential component of a family of tripartite drug and toxin exporters, but for colicin E1, it is essential for its import.

SUBMITTER: Jakes KS 

PROVIDER: S-EPMC5165097 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature