PURIFICATION AND CHARACTERIZATION OF CHLOROPHENOL 4-MONOOXYGENASE FROM BURKHOLDERIA-CEPACIA AC1100

Authors
Citation
Ly. Xun, PURIFICATION AND CHARACTERIZATION OF CHLOROPHENOL 4-MONOOXYGENASE FROM BURKHOLDERIA-CEPACIA AC1100, Journal of bacteriology, 178(9), 1996, pp. 2645-2649
Citations number
25
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Microbiology
Journal title
ISSN journal
0021-9193
Volume
178
Issue
9
Year of publication
1996
Pages
2645 - 2649
Database
ISI
SICI code
0021-9193(1996)178:9<2645:PACOC4>2.0.ZU;2-N
Abstract
Burkholderia (formerly Pseudomonas) cepacia AC1100 mineralizes the her bicide 2,4,5-trichlorophenoxyacetate (2,4,5-T), and the first intermed iate of 2,4,5-T degradation is 2,4,5-trichlorophenol. Chlorophenol 4-m onooxygenase activity responsible for 2,4,5-trichlorophenol degradatio n was detected in the cell extract. The enzyme consisted of two compon ents separated during purification, and both were purified to more tha n 95% homogeneity, The reconstituted enzyme catalyzed the hydroxylatio n of several tested chlorophenols,vith the coconsumption of NADH and o xygen. In addition to chlorophenols, the enzyme also hydroxylated some chloro-p-hydroquinones with the coconsumption of NADH and oxygen. App arently, the single enzyme was responsible for converting 2,4,5-trichl orophenol to 2,5-dichloro-p-hydroquinone and then to 5-chlorohydroxyqu inol (5-chloro-1,2,4-trihydroxybenzene). Component A had a molecular w eight of 22,000 and contained flavin adenine dinucleotide. Component A alone catalyzed NADH-dependent cytochrome c reduction, indicating tha t it had reductase activity. Component B had a molecular weight of 58, 000, and no catalytic activity has yet been shown by itself.