Your browser version may not work well with NCBI's Web applications. More information here...
1: J Biol Chem. 1990 Mar 5;265(7):3628-35.Click here to read Links

Sequence analysis of bovine lens aldose reductase.

Schade SZ, Early SL, Williams TR, Kézdy FJ, Heinrikson RL, Grimshaw CE, Doughty CC.

Department of Biological Chemistry, University of Illinois Health Sciences Center, Chicago 60612.

The covalent structure of bovine lens aldose reductase (alditol-NADP+ oxidoreductase, EC 1.1.1.21) was determined by sequence analysis of peptides generated by specific and chemical cleavage of the homogeneous apoenzyme. Peptides, purified by reverse-phase high performance liquid chromatography were subjected to compositional analysis and sequencing by gas-phase automated Edman degradation. Aldose reductase was found to contain 315 amino acid residues. The enzyme is blocked at the amino terminus, and mass spectrometry was employed to identify the blocking acetyl group and to sequence the amino-terminal tryptic peptide. The aldose reductase was shown to contain no carbohydrate despite the fact that the enzyme contains the consensus sequence -Asn-Lys-Thr- for N-linked glycosylation. Comparative sequence analysis and application of algorithms for prediction of secondary structure and nucleotide binding domains are consistent with the view that aldose reductase is a double-domain protein with a beta-alpha-beta secondary structural organization. The NADPH binding site appears to be associated with the amino-terminal half of the enzyme. Modeling studies based on the tertiary structures of dihydrofolate and glutathione reductases indicate that the NADPH binding site begins at Lys-11 and continues with a beta-alpha-beta fold characteristic of nucleotide binding proteins.

PMID: 2105951 [PubMed - indexed for MEDLINE]