MOLECULAR-CLONING, SEQUENCING AND CHARACTERIZATION OF THE GENES FOR ADENOSYLCOBALAMIN-DEPENDENT DIOL DEHYDRATASE OF KLEBSIELLA-PNEUMONIAE

Klebsiella pneumoniae and some of the other Enterobacteriaceae form bo th diol dehydratase and glycerol dehydratase in response to growth sub strates. To compare these enzymes produced by the same bacterium, the pdd genes of K. pneumoniae encoding adenosylcobalamin-dependent diol d ehydratase were cloned and sequenced. The sequential three open readin g frames (pddA, pddB, and pddC genes) encoded polypeptides of 554, 228 , and 174 amino acid residues with predicted molecular weights of 60,3 79(alpha), 24,401(beta), and 19,489(gamma), respectively. The deduced amino acid sequences of the subunits were 84-100% and 54-71% identical with those reported for diol dehydratases and glycerol dehydratases, respectively.