Kinetic results for mutations of conserved residues H304 and R309 of human sulfite oxidase point to mechanistic complexities.
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ABSTRACT:
SUBMITTER: Davis AC
PROVIDER: S-EPMC4495959 | biostudies-literature | 2014 Sep
REPOSITORIES: biostudies-literature
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Kinetic results for mutations of conserved residues H304 and R309 of human sulfite oxidase point to mechanistic complexities.
Davis Amanda C AC Johnson-Winters Kayunta K Arnold Anna R AR Tollin Gordon G Enemark John H JH
Metallomics : integrated biometal science 20140901 9
Several point mutations in the gene of human sulfite oxidase (hSO) result in isolated sulfite oxidase deficiency, an inherited metabolic disorder. Three conserved residues (H304, R309, K322) are hydrogen bonded to the phosphate group of the molybdenum cofactor, and the R309H and K322R mutations are responsible for isolated sulfite oxidase deficiency. The kinetic effects of the K322R mutation have been previously reported (Rajapakshe et al., Chem. Biodiversity, 2012, 9, 1621-1634); here we invest ...[more]
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