Encyclopedia of Metalloproteins

2013 Edition
| Editors: Robert H. Kretsinger, Vladimir N. Uversky, Eugene A. Permyakov

CusCFBA Copper/Silver Efflux System

  • Megan M. McEvoy
  • Alayna M. George Thompson
Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-1533-6_527



Tripartite efflux complexes are protein export systems that span both membranes in Gram-negative bacteria and are involved in efflux of compounds from the cell. These systems are composed of three proteins: an inner membrane protein, an outer membrane protein, and a periplasmic adaptor that connects the two membrane proteins.

RND proteins are Resistance-nodulation-and cell division proteins. These are membrane proteins that expel compounds from bacterial cells using the protein gradient as an energy source. In Gram-negative tripartite efflux complexes, RND proteins are the inner membrane component.

MFPs are membrane fusion proteins; they function as the adaptors in the tripartite efflux complexes. They are also called periplasmic adaptor proteins.

Periplasm is the region between the inner and outer membranes in Gram-negative bacteria.


Several transition metals are necessary as trace...

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© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Department of Chemistry and BiochemistryUniversity of ArizonaTucsonUSA