1fxi
STRUCTURE OF THE [2FE-2S] FERREDOXIN I FROM THE BLUE-GREEN ALGA APHANOTHECE SACRUM AT 2.2 ANGSTROMS RESOLUTION
Structural highlights
FunctionFER_APHSA Ferredoxins are iron-sulfur proteins that transfer electrons in a wide variety of metabolic reactions. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedCrystals of a [2Fe-2S] ferredoxin (Fd) I with a relative molecular mass of 10,480 were obtained from the blue-green alga Aphanothece sacrum. Each asymmetric unit of the crystal contains four molecules. An electron density map calculated by the single isomorphous replacement method with the anomalous dispersion at 2.5 A resolution was refined by averaging the four molecules in the asymmetric unit. Positional and isotropic thermal parameters for the non-hydrogen atoms of the four molecules and 158 water molecules were refined to an R-factor (R = sigma[Fo-Fc[/sigma Fo) of 0.23 by the restrained least-squares method. The estimated root-mean-square (r.m.s.) error for the atomic positions is 0.3 A. The r.m.s. deviations of equivalent C alpha atoms of the asymmetric-unit molecules superposed by the least-squares method average 0.35 A. The Fd molecule has a structure like the beta-barrel in the molecule of the [2Fe-2S] Fd from Spirulina platensis. A [2Fe-2S] cluster is bonded covalently to the protein molecule by four Fe-S, in which three of the Fe-S bonds are in a loop segment from position 38 to 47. The hydrophobic core inside the beta-barrel is formed by seven conservative residues: Val15, Val18, Ile24, Leu51, Ile74, Ala79 and Ile87. The molecular surface around Tyr23, Tyr80 and the active center may interact with ferredoxin-NADP+ reductase. One of the two iron atoms of the [2Fe-2S] cluster should be more easily reduced than the other because of differences in the hydrogen-bonding scheme and the hydrophobicity around the atoms. Structure of the [2Fe-2S] ferredoxin I from the blue-green alga Aphanothece sacrum at 2.2 A resolution.,Tsukihara T, Fukuyama K, Mizushima M, Harioka T, Kusunoki M, Katsube Y, Hase T, Matsubara H J Mol Biol. 1990 Nov 20;216(2):399-410. PMID:2123937[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences | ||||||||||||||||||||
