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Heavy metal transport by the CusCFBA efflux system.

ABSTRACT: It is widely accepted that the increased use of antibiotics has resulted in bacteria with developed resistance to such treatments. These organisms are capable of forming multi-protein structures that bridge both the inner and outer membrane to expel diverse toxic compounds directly from the cell. Proteins of the resistance nodulation cell division (RND) superfamily typically assemble as tripartite efflux pumps, composed of an inner membrane transporter, a periplasmic membrane fusion protein, and an outer membrane factor channel protein. These machines are the most powerful antimicrobial efflux machinery available to bacteria. In Escherichia coli, the CusCFBA complex is the only known RND transporter with a specificity for heavy metals, detoxifying both Cu(+) and Ag(+) ions. In this review, we discuss the known structural information for the CusCFBA proteins, with an emphasis on their assembly, interaction, and the relationship between structure and function.

SUBMITTER: Delmar JA

PROVIDER: S-EPMC4622206 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Heavy metal transport by the CusCFBA efflux system.

Delmar Jared A JA Su Chih-Chia CC Yu Edward W EW

Protein science : a publication of the Protein Society 20150824 11

It is widely accepted that the increased use of antibiotics has resulted in bacteria with developed resistance to such treatments. These organisms are capable of forming multi-protein structures that bridge both the inner and outer membrane to expel diverse toxic compounds directly from the cell. Proteins of the resistance nodulation cell division (RND) superfamily typically assemble as tripartite efflux pumps, composed of an inner membrane transporter, a periplasmic membrane fusion protein, and ...[more]

PMID: 26258953

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