3nyk
The structure of cobalt-substituted pseudoazurin from Alcaligenes faecalisThe structure of cobalt-substituted pseudoazurin from Alcaligenes faecalis
Structural highlights
Function[AZUP_ALCFA] This soluble electron transfer copper protein is required for the inactivation of copper-containing nitrite reductase in the presence of oxygen. Serves as a direct electron donor to the nitrite reductase. Publication Abstract from PubMedThe Cu(II) center at the active site of the blue copper protein pseudoazurin from Alcaligenes faecalis has been substituted by Co(II) via denaturing of the protein, chelation and removal of copper by EDTA and refolding of the apo-protein, followed by addition of an aqueous solution of CoCl(2). Sitting drop vapour diffusion experiments produced green hexagonal crystals, which belong to space group P6(5), with unit cell dimensions a = b = 50.03, c =98.80 A. Diffraction data, collected at 291 K on a copper rotating anode X-ray source, were phased by the anomalous signal of the cobalt atom. The structure was built automatically, fitted manually and subsequently refined to 1.86 A resolution. The Co-substituted protein exhibits similar overall geometry to the native structure with copper. Cobalt binds more strongly to the axial Met86-Sdelta and retains the tetrahedral arrangement with the four ligand atoms, His40-Ndelta(1), Cys78-Sgamma, His81-Ndelta(1) and 86Met-Sdelta, although the structure is less distorted than the native copper protein. The structure reported herein, is the first crystallographic structure of a Co(II)-substituted pseudoazurin. (c) 2010 Wiley Periodicals, Inc. Biopolymers, 2010. The crystal structure of cobalt-substituted pseudoazurin from Alcaligenes faecalis.,Gessmann R, Kyvelidou C, Papadovasilaki M, Petratos K Biopolymers. 2010 Oct 13. PMID:20945335[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
| ||||||||||||||||||