1etj
AZURIN MUTANT WITH MET 121 REPLACED BY GLUAZURIN MUTANT WITH MET 121 REPLACED BY GLU
Structural highlights
FunctionAZUR_PSEAE Transfers electrons from cytochrome c551 to cytochrome oxidase. 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 PubMedThe Met121Glu azurin mutant has been crystallized and the structure determined at a resolution of 2.3 A. In the crystal structure a carboxyl oxygen of Met121Glu is coordinated to the metal at a distance of 2.2 A. Single-crystal resonance Raman spectroscopy was used to show that the glutamic acid residue in the copper site was in the protonated state. Titration of this residue gives rise to a number of unusual, pH-dependent properties: as the pH is increased from 4 to 8, the S(Cys)-Cu ligand-to-metal charge transfer bands are blue shifted and their intensity ratio is reversed, the EPR signal changes from type 1 copper to a new form of protein-bound copper, and the redox potential changes from 370 to 180 mV. The spectroscopic changes in this pH interval are consistent with a two-state model. From the pH dependence of the optical and EPR spectra, pKa = 5.0 for the glutamic acid in the oxidized protein was determined. X-ray structure determination and characterization of the Pseudomonas aeruginosa azurin mutant Met121Glu.,Karlsson BG, Tsai LC, Nar H, Sanders-Loehr J, Bonander N, Langer V, Sjolin L Biochemistry. 1997 Apr 8;36(14):4089-95. PMID:9100002[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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