Spectroscopic and biochemical studies on protein variants of quinaldine 4-oxidase: Role of E736 in catalysis and effects of serine ligands on the FeSI and FeSII clusters.

@article{Kappl2006SpectroscopicAB,
  title={Spectroscopic and biochemical studies on protein variants of quinaldine 4-oxidase: Role of E736 in catalysis and effects of serine ligands on the FeSI and FeSII clusters.},
  author={R. Kappl and Sonja Sielker and K. Ranguelova and J. Wegner and K. Parschat and J. Hüttermann and S. Fetzner},
  journal={Biochemistry},
  year={2006},
  volume={45 49},
  pages={
          14853-68
        }
}
Quinaldine 4-oxidase (Qox), which catalyzes the hydroxylation of quinaldine to 1H-4-oxoquinaldine, is a heterotrimeric (LMS)2 molybdo-iron/sulfur flavoprotein belonging to the xanthine oxidase family. Variants of Qox were generated by site-directed mutagenesis. Replacement in the large subunit at E736, which is presumed to be located close to the molybdenum, by aspartate (QoxLE736D) resulted in a marked decrease in kcat app for quinaldine, while Km app was largely unaffected. Although a minor… Expand
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