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The structure of an N11A mutant of the G-protein domain of FeoB.

ABSTRACT: The uptake of ferrous iron in prokaryotes is mediated by the G-protein-coupled membrane protein FeoB. The protein contains two N-terminal soluble domains that are together called `NFeoB'. One of these is a G-protein domain, and GTP hydrolysis by this domain is essential for iron transport. The GTPase activity of NFeoB is accelerated in the presence of potassium ions, which bind at a site adjacent to the nucleotide. One of the ligands at the potassium-binding site is a conserved asparagine residue, which corresponds to Asn11 in Streptococcus thermophilus NFeoB. The structure of an N11A S. thermophilus NFeoB mutant has been determined and refined to a resolution of 1.85 Å; the crystals contained a mixture of mant-GDP-bound and mant-GMP-bound protein. The structure demonstrates how the use of a derivatized nucleotide in cocrystallization experiments can facilitate the growth of diffraction-quality crystals.

SUBMITTER: Ash MR

PROVIDER: S-EPMC3232127 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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The structure of an N11A mutant of the G-protein domain of FeoB.

Ash Miriam Rose MR Maher Megan J MJ Guss J Mitchell JM Jormakka Mika M

Acta crystallographica. Section F, Structural biology and crystallization communications 20111129 Pt 12

The uptake of ferrous iron in prokaryotes is mediated by the G-protein-coupled membrane protein FeoB. The protein contains two N-terminal soluble domains that are together called `NFeoB'. One of these is a G-protein domain, and GTP hydrolysis by this domain is essential for iron transport. The GTPase activity of NFeoB is accelerated in the presence of potassium ions, which bind at a site adjacent to the nucleotide. One of the ligands at the potassium-binding site is a conserved asparagine residu ...[more]

PMID: 22139154

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