| Affiliation: | (1) Divisions of Applied Life Sciences, Kyoto University, Japan;(2) Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan;(3) Institut für Technische Biochemie, Universität Stuttgart, Allmandring 31, D-70459 Stuttgart, Germany;(4) Present address: Biotechnology Research Center, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Kosugi, Toyama 939-0398, Japan |
| Abstract: | The metabolism of polychlorinated dibenzo-p-dioxins by cytochrome P450 BM-3 from Bacillus megaterium and a mutant enzyme of it (AL4V; Ala74Gly, Phe87Val, Leu188Gln triple mutant) was examined. Both purified enzymes metabolized 1-monochloro-, 2,3-dichloro-, and 2,3,7-trichloro-dibenzo-p-dioxin, but not 2,3,7,8-tetrachloro-dibenzo-p-dioxin. The mutant AL 4V had 2–12 times higher activity than the wild-type P450 BM-3 towards polychlorinated dibenzo-p-dioxins. The products were hydroxylated at an unsubstituted position and/or showing migration of the chloride and were less toxic derivatives with lower than 10% toxicity of the original compounds.Revisions requested 26 August 2004; Revisions received 15 October 2004 |
