PROPERTIES AND SEQUENCE OF THE COENZYME B-12-DEPENDENT GLYCEROL DEHYDRATASE OF CLOSTRIDIUM-PASTEURIANUM

The genes encoding coenzyme B-12-dependent glycerol dehydratase of Clo s:Clostridium pasteurianum were subcloned and expressed in Escherichia coli. The native molecular mass of the enzyme is 190 000 Da. The enzy me converts glycerol, 1,2-propanediol and 1.2-ethanediol to 3-hydroxyp ropionaldehyde, propionaldehyde and acetaldehyde, respectively, but gl ycerol is the preferred substrate. The nucleotide sequences of the dha BCE genes encoding the three subunits of glycerol dehydratase and of o rfZ whose function is unknown were determined. The deduced products of the dhaBCE genes with calculated molecular masses of 60 813. 19 549 a nd 16 722 Da, respectively, revealed high similarity to amino acid seq uences of subunits of coenzyme B-12-dependent glycerol and diol dehydr atases from other organisms. (C) 1998 Federation of European Microbiol ogical Societies. Published by Elsevier Science B.V. All rights reserv ed.