OXIDATION OF ALIPHATIC OLEFINS BY TOLUENE DIOXYGENASE - ENZYME RATES AND PRODUCT IDENTIFICATION

Toluene dioxgenase from Pseudomonas putida F1 has been studied extensi vely with aromatic substrates. The present work examined the toluene d ioxgenase-catalyzed oxidation of various halogenated ethenes, propenes , butenes and nonhalogenated cis-2-pentene, an isomeric mix of 2-hexen es, cis-2-heptene, and cis-2-octene as substrates for toluene dioxygen ase, Enzyme specific activities were determined for the more water-sol uble C-2 to C-5 compounds and ranged from <4 to 52 nmol per min per mg of protein, Trichloroethene was oxidized at a rate of 33 nmol per min per mg of protein. Products from enzyme reactions were identified by gas chromatography-mass spectrometry. Proton and carbon nuclear magnet ic resonance spectroscopy of compounds from whole-cell incubation conf irmed the identity of products, Substrates lacking a halogen substitue nt on sp(2) carbon atoms were dioxygenated, while those with halogen a nd one or more unsubstituted allylic methyl groups were monooxygenated to yield allylic alcohols, 2,3-Dichloro-1-propene, containing both a halogenated double bond and a halogenated allylic methyl group, underw ent monooxygenation with allelic rearrangement to yield an isomeric mi xture of cis- and trans-2,3-dichloro-2-Dropene-1-ol.