Catalytic activity of Pseudomonas putida strain G7 naphthalene 1,2-dioxygenase on biphenyl

Naphthalene dioxygenase (NAP dox) catalyzes the first reaction of the napht halene catabolic pathway encoded by the NAH plasmid. Similar to other aryl hydroxylating dioxygenases, NAP dox introduces molecular oxygen on two vici nal carbons of the aromatic ring. In this work it is shown that Pseudomonas putida G7 NAP dox (NAP dox(G7)) can catalyze the oxygenation of biphenyl q uite efficiently. Similar to biphenyl dioxygenase which is the homologous r eaction of the biphenyl catabolic pathway, the enzyme attack biphenyl molec ule onto the ortho-meta carbons preferentially. However, unlike biphenyl di oxygenase of Pseudomonas sp. LB400, NAP dox(G7) dioxygenates a non negligib le portion of the substrate onto the meta-para carbons. (C) 1999 Elsevier S cience Ltd. All rights reserved.