Conversion of the coenzyme specificity of isocitrate dehydrogenase by module replacement.
The coenzyme specificity of isocitrate dehydrogenase from an extreme thermophilic bacterium was converted from NADP-dependent to NAD-dependent by replacing a "module" involved in the coenzyme binding site. The conversion was not possible with the replacement of a few residues that interact with the coenzyme. In addition, the module-replaced mutant dehydrogenase was as stable as the original, wild type enzyme. The results support a previous hypothesis that a module is a structural and functional unit of a protein.
Yaoi
T
T
Department of Life Science, Tokyo Institute of Technology, Yokohama.
Miyazaki
K
K
Oshima
T
T
Komukai
Y
Y
Go
M
M
D000595:Amino Acid Sequence; D004795:Enzyme Stability; D007521:Isocitrate Dehydrogenase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D007700:Kinetics; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009243:NAD / Q000378:metabolism*; D009249:NADP / Q000378:metabolism*; D017354:Point Mutation; D011487:Protein Conformation; D015202:Protein Engineering; D017433:Protein Structure, Secondary; D016963:Thermus thermophilus / Q000201:enzymology / Q000235:genetics
D009243:NAD; D009249:NADP; D007521:Isocitrate Dehydrogenase