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Low temperature 65Cu NMR spectroscopy of the Cu+ site in azurin.

ABSTRACT: (65)Cu central-transition NMR spectroscopy of the blue copper protein azurin in the reduced Cu(I) state, conducted at 18.8 T and 10 K, gave a strongly second order quadrupole perturbed spectrum, which yielded a (65)Cu quadrupole coupling constant of +/-71.2 +/- 1 MHz, corresponding to an electric field gradient of +/-1.49 atomic units at the copper site, and an asymmetry parameter of approximately 0.2. Quantum chemical calculations employing second order Møller-Plesset perturbation theory and large basis sets successfully reproduced these experimental results. Sensitivity and relaxation times were quite favorable, suggesting that NMR may be a useful probe of the electronic state of copper sites in proteins.

SUBMITTER: Lipton AS

PROVIDER: S-EPMC2782662 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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Low temperature 65Cu NMR spectroscopy of the Cu+ site in azurin.

Lipton Andrew S AS Heck Robert W RW de Jong Wibe A WA Gao Amy R AR Wu Xiongjian X Roehrich Adrienne A Harbison Gerard S GS Ellis Paul D PD

Journal of the American Chemical Society 20091001 39

(65)Cu central-transition NMR spectroscopy of the blue copper protein azurin in the reduced Cu(I) state, conducted at 18.8 T and 10 K, gave a strongly second order quadrupole perturbed spectrum, which yielded a (65)Cu quadrupole coupling constant of +/-71.2 +/- 1 MHz, corresponding to an electric field gradient of +/-1.49 atomic units at the copper site, and an asymmetry parameter of approximately 0.2. Quantum chemical calculations employing second order Møller-Plesset perturbation theory and la ...[more]

PMID: 19746904

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