4rh4
Zinc-substituted pseudoazurin solved by S/Zn-SAD phasingZinc-substituted pseudoazurin solved by S/Zn-SAD phasing
Structural highlights
FunctionAZUP_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 copper(II) centre of the blue copper protein pseudoazurin from Alcaligenes faecalis has been substituted by zinc(II) via denaturing the protein, chelation and removal of copper and refolding the apoprotein, followed by the addition of an aqueous solution of ZnCl2. Vapour-diffusion experiments produced colourless hexagonal crystals (space group P65), which when cryocooled had unit-cell parameters a = b = 49.01, c = 98.08 A. Diffraction data collected at 100 K using a copper sealed tube were phased by the weak anomalous signal of five S atoms and one Zn atom. The structure was fitted manually and refined to 1.6 A resolution. The zinc-substituted protein exhibits similar overall geometry to the native structure with copper. Zn(2+) binds more strongly to its four ligand atoms (His40 N(delta1), Cys78 S(gamma), His81 N(delta1) and Met86 S(delta)) and retains the tetrahedral arrangement, although the structure is less distorted than the native copper protein. Zinc-substituted pseudoazurin solved by S/Zn-SAD phasing.,Gessmann R, Papadovasilaki M, Drougkas E, Petratos K Acta Crystallogr F Struct Biol Commun. 2015 Jan 1;71(Pt 1):19-23. doi:, 10.1107/S2053230X14025552. Epub 2015 Jan 1. PMID:25615962[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
| ||||||||||||||||