2B08

Reduced acetamide-bound M150G Nitrite Reductase from Alcaligenes faecalis

Summary for 2B08

• Entry DOI: 10.2210/pdb2b08/pdb
• Descriptor: Copper-containing nitrite reductase, COPPER (I) ION, ACETAMIDE, ... (4 entities in total)
• Functional Keywords: axial methionine, reorganization energy, met62, allosteric control, acetamide, oxidoreductase
• Biological source: Alcaligenes faecalis
• Cellular location: Periplasm: P38501
• Total number of polymer chains: 3
• Total formula weight: 111008.65

Authors

Wijma, H.J.,MacPherson, I.S.,Farver, O.,Tocheva, E.I.,Pecht, I.,Verbeet, M.Ph.,Murphy, M.E.P.,Canters, G.W. (deposition date: 2005-09-13, release date: 2006-09-26, Last modification date: 2024-02-14)

Primary citation

Wijma, H.J.,MacPherson, I.,Farver, O.,Tocheva, E.I.,Pecht, I.,Verbeet, M.P.,Murphy, M.E.P.,Canters, G.W.
Effect of the methionine ligand on the reorganization energy of the type-1 copper site of nitrite reductase.
J.Am.Chem.Soc., 129:519-525, 2007

PubMed Abstract: Copper-containing nitrite reductase harbors a type-1 and a type-2 Cu site. The former acts as the electron acceptor site of the enzyme, and the latter is the site of catalytic action. The effect of the methionine ligand on the reorganization energy of the type-1 site was explored by studying the electron-transfer kinetics between NiR (wild type (wt) and the variants Met150Gly and Met150Thr) with Fe(II)EDTA and Fe(II)HEDTA. The mutations increased the reorganization energy by 0.3 eV (30 kJ mol-1). A similar increase was found from pulse radiolysis experiments on the wt NIR and three variants (Met150Gly, Met150His, and Met150Thr). Binding of the nearby Met62 to the type-1 Cu site in Met150Gly (under influence of an allosteric effector) lowered the reorganization energy back to approximately the wt value. According to XRD data the structure of the reduced type-1 site in Met150Gly NiR in the presence of an allosteric effector is similar to that in the reduced wt NiR (solved to 1.85 A), compatible with the similarity in reorganization energy.

PubMed: 17227014
DOI: 10.1021/ja064763j

Experimental method

X-RAY DIFFRACTION (1.9 Å)