Analysis of amino acid residues involved in cold activity of monomeric isocitrate dehydrogenase from psychrophilic bacteria, Colwellia maris and Colwellia psychrerythraea(ENZYMOLOGY, PROTEIN ENGINEERING, AND ENZYME TECHNOLOGY)

スポンサーリンク

概要

• 論文の詳細を見る

• Monomeric isocitrate dehydrogenases from psychrophilic bacteria, Colwellia mans and Colwellia psychrerythraea (CmIDH-II and CpIDH-M, respectively) are cold-adapted enzymes and show a high degree of amino acid sequential identity to each other (77%). However, maximum activity of CpIDH-M at optimum temperature is much less than that of CmIDH-II. In the C-terminal region 3 of these enzymes, which was suggested from previous study to be responsible for their distinct catalytic ability, several sequential differences of amino acid residue are present. Among them, ten amino acid residues were exchanged between them by site-directed mutagenesis and several properties of the mutated enzymes were examined in this study. The mutated enzymes of CmIDH-II substituted its Gln671, Leu724 and Phe735 residues with the corresponding residues of CpIDH-M (termed Q671K, L724Q and F735L, respectively) showed lower specific activity and thermostability for activity than the wild-type enzyme. Furthermore, the decreased specific activity was also observed in L693F. In contrast, the corresponding mutants of CpIDH-M, F693L, Q724L and L735F, showed the increased specific activity and thermostability for activity. The catalytic efficiency (k_<cat>/K_m) values of these mutated CmIDH-II and CpIDH-M were lower and higher than those of their wild-type IDHs, respectively. These results suggest that the Gln671, Leu693, Leu724 and Phe735 residues of CmIDH-II are important for exerting its high catalytic ability.

• 公益社団法人日本生物工学会の論文

著者

• Takada Yasuhiro

  Department Of Biological Sciences Faculty Of Science Hokkaido University

• Kobayashi Miyuki

  Biosystems Science Course, Graduate School of Life Science, Hokkaido University

• Yasuda Wataru

  Biosystems Science Course, Graduate School of Life Science, Hokkaido University

関連論文

• Membrane-bound ATPase of a Psychrophilic Marine Bacterium, Vibrio sp. Strain ABE-1
• Identification of Respiratory Quinones from a Psychrophilic Bacterium, Vibrio sp. Strain ABE-1(Microbiology & Fermentation Industry)
• Respiration-Dependent Proton and Sodium Pumps in a Psychrophilic Bacterium, Vibrio Sp. Strain ABE-1
• A Survey of Patients with Inflammatory Skin Recurrence Corresponding to the Area of Previous Irradiation after Postoperative Radiotherapy for Breast Cancer
• Cloning and Expression of the Isocitrate Lyase Gene from a Nitrogen-Fixing Bacterium, Azotobacter vinelandii, and Functional Analysis of the Enzyme by Site-Directed Mutagenesis
• Long-term Sequential Changes of Radiation Proctitis and Angiopathy in Rats
• Analysis of amino acid residues involved in cold activity of monomeric isocitrate dehydrogenase from psychrophilic bacteria, Colwellia maris and Colwellia psychrerythraea(ENZYMOLOGY, PROTEIN ENGINEERING, AND ENZYME TECHNOLOGY)
• Analysis of the Amino Acid Residues Involved in the Thermal Properties of the Monomeric Isocitrate Dehydrogenases of the Psychrophilic Bacterium Colwellia maris and the Mesophilic Bacterium Azotobacter vinelandii

スポンサーリンク