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MoV electron paramagnetic resonance of sulfite oxidase revisited: the low-pH chloride signal.

ABSTRACT: Valuable information on the active sites of molybdenum enzymes has been provided by Mo(V) electron paramagnetic resonance (EPR) spectroscopy. In recent years, multiple resonance techniques have been extensively used to examine details of the active-site structure, but basic continuous-wave (CW) EPR has not been re-evaluated in several decades. Here, we present a re-examination of the CW EPR spectroscopy of the sulfite oxidase low-pH chloride species and provide evidence for direct coordination of molybdenum by chloride.

SUBMITTER: Doonan CJ

PROVIDER: S-EPMC2841525 | biostudies-literature | 2008 Mar

REPOSITORIES: biostudies-literature

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MoV electron paramagnetic resonance of sulfite oxidase revisited: the low-pH chloride signal.

Doonan Christian J CJ Wilson Heather L HL Bennett Brian B Prince Roger C RC Rajagopalan K V KV George Graham N GN

Inorganic chemistry 20080214 6

Valuable information on the active sites of molybdenum enzymes has been provided by Mo(V) electron paramagnetic resonance (EPR) spectroscopy. In recent years, multiple resonance techniques have been extensively used to examine details of the active-site structure, but basic continuous-wave (CW) EPR has not been re-evaluated in several decades. Here, we present a re-examination of the CW EPR spectroscopy of the sulfite oxidase low-pH chloride species and provide evidence for direct coordination o ...[more]

PMID: 18271529

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Characterization of chloride-depleted human sulfite oxidase by electron paramagnetic resonance spectroscopy: experimental evidence for the role of anions in product release.

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Electron-paramagnetic-resonance parameters of molybdenum(V) in sulphite oxidase from chicken liver.

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