Jump to main content
Jump to site search

Issue 12, 2013
Previous Article Next Article

Phylogenomic analysis of Cation Diffusion Facilitator proteins uncovers Ni2+/Co2+ transporters

Author affiliations

Abstract

The ubiquitous Cation Diffusion Facilitator proteins (CDF) play a key role in maintaining the cellular homeostasis of essential metal ions. Previous neighbor-joining phylogenetic analysis classified CDF proteins into three substrate-defined groups: Zn2+, Fe2+/Zn2+ and Mn2+. These studies were unable to discern substrate-defined clades for Ni2+, Co2+, Cd2+ and Cu2+ transporters, despite their existence in this family. In this study we improved the accuracy of this previous functional classification using a phylogenomic approach based on a thorough maximum-likelihood phylogeny and the inclusion of recently characterized CDF transporters. The inference of CDF protein function predicted novel clades for Zn2+, Fe2+, Cd2+ and Mn2+. The Ni2+/Co2+ and Co2+ substrate specificities of two clades containing uncharacterized proteins were defined through the functional characterization of nepA and cepA metal inducible genes which independently conferred Ni2+ and Co2+ resistances to Rhizobium etli CFN42 and increased, respectively, Ni2+/Co2+ and Co2+ resistances to Escherichia coli. Neither NepA nor CepA confer Zn2+, Fe2+ and Mn2+ resistances. The ability of NepA to confer Ni2+/Co2+ resistance is dependent on clade-specific residues Asn88 and Arg197 whose mutations produce a non-functional protein.

Graphical abstract: Phylogenomic analysis of Cation Diffusion Facilitator proteins uncovers Ni2+/Co2+ transporters

Back to tab navigation

Supplementary files

Publication details

The article was received on 25 Jul 2013, accepted on 06 Sep 2013 and first published on 09 Sep 2013


Article type: Paper
DOI: 10.1039/C3MT00204G
Metallomics, 2013,5, 1634-1643

  •   Request permissions

    Phylogenomic analysis of Cation Diffusion Facilitator proteins uncovers Ni2+/Co2+ transporters

    C. Cubillas, P. Vinuesa, M. L. Tabche and A. García-de los Santos, Metallomics, 2013, 5, 1634
    DOI: 10.1039/C3MT00204G

Search articles by author

Spotlight

Advertisements