Human carbonyl reductase. Nucleotide sequence analysis of a cDNA and amino acid sequence of the encoded protein.

Carbonyl reductase (EC 1.1.1.184) is one of several monomeric, NADPH-dependent oxidoreductases having wide specificity for carbonyl compounds that are generally referred to as the aldoketoreductases. The grouping of the enzyme into the family has been proposed on the basis of functional similarities and in the absence of structural data. Here, we describe the isolation and characterization of a cDNA clone complementary to human carbonyl reductase mRNA from a human placenta cDNA library constructed in phage lambda gt11. The cDNA consists of 1199 base pairs and contains an open reading frame encoding a protein comprised of 277 amino acids with a Mr of 30,375. The predicted amino acid sequence was confirmed by partial sequence analysis of the carbonyl reductase protein. Comparison of the protein sequence with the primary structures of other aldoketoreductases revealed no significant homologies. A possible homology, on the other hand, exists between carbonyl reductase and "short" subunit alcohol/polyol dehydrogenases.