1.3.98.1 C130A low activity with dihydroorotate, increasing activity above pH 8.0 with dihydrooxonate 390913 1.3.98.1 C130A the mutant enzyme exhibits binding affinities for dihydroorotate similar to that of the wild type enzyme, reduction is extremely slow compared to that of the wild type, the rate of reduction increases with pH showing no sign of a plateau 685146 1.3.98.1 C130A the mutant forms charge-transfer complexes upon binding 3,4-dihydroxybenzoate, but the maximum of the broad charge-transfer bands is shifted to 590 nm 685158 1.3.98.1 C130S the mutant enzyme exhibits binding affinities for dihydroorotate similar to that of the wild type enzyme, reduction is extremely slow compared to that of the wild type, the rate of reduction increases with pH showing no sign of a plateau 685146 1.3.98.1 C130S the mutant forms charge-transfer complexes upon binding 3,4-dihydroxybenzoate, but the maximum of the broad charge-transfer bands is shifted to 610 nm 685158 1.3.98.1 E206/K296E conversion of intermolecular salt bridge, mutant is fully active in concentrated solutions and dissociates into monomers upon dilution like wild-type enzyme 657291 1.3.98.1 E206A disturbance of intermolecular salt bridge, mutant retains almost complete activity 657291 1.3.98.1 E206K disturbance of intermolecular salt bridge, mutant activity is severely impaired 657291 1.3.98.1 H185A 4fold increase in KM-value of CoQD, 50% increase in KM-value of L-dihydroorotate 656285 1.3.98.1 K136E little changes in activity 656148