Site-directed mutagenesis dioxygenase

The coordination of the Rieske cluster in the a subunit of benzene dioxygenase has been studied by site-directed mutagenesis. The replacement of His 98 or His 119 (corresponding to His 83/104 in NDO) by Cys resulted in a protein that was unable to coordinate a normal Rieske-type cluster (53). In the mutant His 98 Cys, a novel EPR spectrum with av = 1-94 was detected that is intermediate between... 

Fischer, F., and Fetzner, S., Site-Directed Mutagenesis of Potential Catalytic Residues in lh-3-Hydroxy-4-Oxoquinoline 2, 4-Dioxygenase, and Hypothesis on the Catalytic Mechanism of 2, 4-Dioxygenolytic Ring Cleavage. FEMS Microbiol Lett, 2000. 190 pp. 21-27. 

Siroheme-comaining enzymes, 47 92 Site-directed mutagenesis dioxygenase, 47 112-113 EPR, 47 450-461... 

Erickson, B.D. Mondello, F.J. (1993). Enhanced biodegradation of polychlorinated biphenyls after site-directed mutagenesis of a biphenyl dioxygenase gene. Applied and Environmental Microbiology, 59, 3858-62. 

Evidence for the involvement of histidine residues in the active site has been obtained from a number of experiments. Treatment with the histidine-selective reagent diethyl pyrocarbonate causes complete loss of activity in prolyl 4-hydroxylase (EC 1.14.11.2) [215] and 2,-4-dichlorophenoxyacetate dioxygenase (TfdA) (EC 1.13.11 group) [211], Site-directed mutagenesis of some of the conserved His residues in prolyl 4-hydroxylase [216] and aspartyl P-hydroxylase (EC 1.14.11.16) [217] also results in the loss of enzymatic activity. More recently, direct spectroscopic evidence for His coordination has been obtained in ESEEM studies of Cu(II)-substituted TfdA [218],... 

Biphenyl dioxygenase P. pseudoalcaligenes KF707 Site-directed mutagenesis T376A/V/F/L T376F Novel ability to oxidize dibenzofuran Enhanced (KF707 enzyme) activities toward various polychlorinated biphenyls [24]... 

Tetrachlorobenzene Rdstonia sp. PC12 Site-directed dioxygenase mutagenesis... 

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