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2328266 
Journal Article 
Purification of hydroxyquinol 1,2-dioxygenase and maleylacetate reductase: The lower pathway of 2,4,5-trichlorophenoxyacetic acid metabolism by Burkholderia cepacia AC1100 
Daubaras, DL; Saido, K; Chakrabarty, AM 
1996 
Yes 
Applied and Environmental Microbiology
ISSN: 0099-2240
EISSN: 1098-5336 
American Society for Microbiology 
UNITED STATES 
62 
11 
4276-4279 
English 
8900023 
WOS:A1996VQ85900062 
The enzyme hydroxyquinol 1,2-dioxygenase, which catalyzes ortho cleavage of hydroxyquinol (1,2,4-trihydroxybenzene) to produce maleylacetate, was purified from Escherichia coli cells containing the tftH gene from Burkholderia cepacia AC1100. Reduction of the double bond in maleylacetate is catalyzed by the enzyme maleylacetate reductase, which was also purified from E. coli cells, these cells containing the tftE gene from B. cepacia AC1100. The two enzymes together catalyzed the conversion of hydroxyquinol to 3-oxoadipate. The purified hydroxyquinol 1,2-dioxygenase was specific for hydroxyquinol and was not able to use catechol, tetrahydroxybenzene, 6-chlorohydroxyquinol, or 5-chlorohydroxyquinol as its substrate. The native molecular mass of hydroxyquinol 1,2-dioxygenase was 68 kDa, and the subunit size of the protein was 36 kDa, suggesting a dimeric protein of identical subunits. 
Oxidoreductases Acting on CH-CH Group Donors; Recombinant Proteins; Genes, Bacterial; Oxygenases; Burkholderia cepacia; Kinetics; Index Medicus; Substrate Specificity; Protein Conformation; Biodegradation, Environmental; Dioxygenases; Oxidoreductases; 2,4,5-Trichlorophenoxyacetic Acid; Escherichia coli; Molecular Weight