Construction and characterization of mutant water-soluble PQQ glucose dehydrogenases with altered K(m) values--site-directed mutagenesis studies on the putative active site.

  title={Construction and characterization of mutant water-soluble PQQ glucose dehydrogenases with altered K(m) values--site-directed mutagenesis studies on the putative active site.},
  author={Satoshi. Igarashi and Takafumi Ohtera and Hiromi Yoshida and Arief Budi Witarto and Koji Sode},
  journal={Biochemical and biophysical research communications},
  volume={264 3},
  • S. IgarashiT. Ohtera K. Sode
  • Published 2 November 1999
  • Biology, Chemistry
  • Biochemical and biophysical research communications
Based on a PCR mutant enzyme of water-soluble glucose dehydrogenase-harboring pyrroloquinoline quinone as the prosthetic group, PQQGDH-B, a site-directed mutagenesis study was carried out. The substitution of Glu277 residue with Gly resulted in a decrease in the K(m) value for glucose and altered the substrate specificity profile, compared with the wild-type enzyme. Mutational analyses on the neighboring amino acid residues of Glu277 were also carried out and constructed Asp275Glu, Asp276Glu… 

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