Characterization of a novel cis-benzene dihydrodiol dehydrogenase from Pseudomonas putida ML2

A second and novel cis-benzene dihydrodiol dehydrogenase which is able to d ehydrogenate a range of cis-dihydrodiols and other vicinal alcohols has bee n purified from Pseudomonas putida ML2. The enzyme is a tetramer of a polyp eptide of 39 kDa in molecular mass and has a pH optimum of 9.0. Despite hav ing a primary structure that has significant similarity to glycerol dehydro genases, the k(cat)/K-m value of the enzyme for cis-benzene dihydrodiol is 4300-fold higher compared to glycerol. The apparent K-m values of the enzym e for cis-benzene dihydrodiol and glycerol are 0.01 mM and 96 mM, respectiv ely, and 0.22 mM for NAD(+). (C) 1999 Federation of European Biochemical So cieties.