PMID: 10700284 , Related PDB ids: 1EBF, 1EBU

Authors:

DeLaBarre B, Thompson PR, Wright GD, Berghuis AM

Title:

Crystal structures of homoserine dehydrogenase suggest a novel catalytic mechanism for oxidoreductases.

Journal:

Nat Struct Biol. 2000 Mar;7(3):238-44.

Abstract:

The structure of the antifungal drug target homoserine dehydrogenase (HSD) was determined from Saccharomyces cerevisiae in apo and holo forms, and as a ternary complex with bound products, by X-ray diffraction. The three forms show that the enzyme is a dimer, with each monomer composed of three regions, the nucleotide-binding region, the dimerization region and the catalytic region. The dimerization and catalytic regions have novel folds, whereas the fold of the nucleotide-binding region is a variation on the Rossmann fold. The novel folds impose a novel composition and arrangement of active site residues when compared to all other currently known oxidoreductases. This observation, in conjunction with site-directed mutagenesis of active site residues and steady-state kinetic measurements, suggest that HSD exhibits a new variation on dehydrogenase chemistry.