Temperature Dependence of Kinetic Parameters for Hyperthermophilic Glutamate Dehydrogenase from Aeropyrum pernix K1.

DOI Web Site Web Site PubMed 1 Citations 21 References Open Access
  • BHUIYA Mohammad W.
    <i>Department of Biological Science and Technology, Faculty of Engineering, The University of Tokushima</i>
  • SAKURABA Haruhiko
    <i>Department of Biological Science and Technology, Faculty of Engineering, The University of Tokushima</i>
  • OHSHIMA Toshihisa
    <i>Department of Biological Science and Technology, Faculty of Engineering, The University of Tokushima</i>

Bibliographic Information

Other Title
  • Temperature Dependence of Kinetic Parameters for Hyperthermophilic Glutamate Dehydrogenase from<i>Aeropyrum pernix</i>K1

Search this article

Description

  The temperature dependence of the steady-state kinetic parameters for a glutamate dehydrogenase from Aeropyrum pernix K1 was investigated. The enzyme showed a biphasic kinetic characteristic for L-glutamate and a monophasic one for NADP at 50–90°C. At low concentrations of L-glutamate the Km decreased from 2.02 to 0.56 mM and the catalytic efficiency (Vmax/Km) markedly increased (4–150 μmol•mg−1•mM−1) along with the increase of temperature from 50 to 90°C. At high concentrations of the substrate the Km was fairly high and approximately constant (around 225 mM), and the catalytic efficiency was low and its temperature-dependent change was small. The Km (0.039 mM) for NADP did not change with the increase of temperature. In the reductive amination, the Kms for 2-oxoglutarate (1.81 and 9.37 mM at low and high levels of ammonia, respectively) were independent on temperature, but the Kms for ammonia and NADPH rose from 86 to 185 mM and 0.050 to 0.175 mM, respectively.<br>

Journal

Citations (1)*help

See more

References(21)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top