Protein Engineering, Vol. 15, No. 7, 611-617,
July 2002
© 2002 Oxford University Press
Cloning and sequence analysis of D-erythrulose reductase from chicken: its close structural relation to tetrameric carbonyl reductases
1 National Institute of Agrobiological Sciences, Kannondai 2–1–2, Tsukuba, Ibaraki 305-8602, 3 Wood Research Institute, Kyoto University, Uji, Kyoto 611-0011 and 4 Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
Sequence analysis of a cDNA for D-erythrulose reductase from chicken liver showed that the deduced open reading frame encodes the protein with a molecular mass of 26 kDa consisting of 246 amino acids. Although the reductase shares more than 60% identity in the amino acid sequence with the mouse tetrameric carbonyl reductase, these two enzymes have many biochemical differences; their substrate specificity, subcellular localization, organ distribution, etc. A three-dimensional structure of D-erythrulose reductase was predicted by comparative modeling based on the structure of the tetrameric carbonyl reductase (PDB entry = 1CYD). Most of the residues at the active site (within 4 Å from the ligand) of the carbonyl reductase were also conserved in the D-erythrulose reductase. Nevertheless, Val190 and Leu146 in the active site of the tetrameric carbonyl reductase were substituted in the D-erythrulose reductase by Asn192 and His148, respectively. The substitutions in the active sites may be related to the difference in substrate specificity of the two enzymes. The phylogenic analysis of D-erythrulose reductase and the other related proteins suggests that the protein described as a carbonyl reductase D-erythrulose reductase.