Presteady State Kinetic Analysis of Riboflavin Synthase

Pre-steady-state kinetic analysis of riboflavin synthase using a pentacyclic reaction intermediate as substrate.

Riboflavin synthase catalyses a mechanistically complex dismutation affording riboflavin and 5-amino-6-ribitylamino-2,4(1H,3H )-pyrimidinedione from 6,7-dimethyl-8-ribityllumazine. A pentacyclic adduct (compound 2 ) of two substrate molecules was used as substrate for pre-steady-state kinetic analysis. Whereas the wild-type enzyme catalyses the decomposition of compound 2 into a mixture of ribo...

Biosynthesis of riboflavin. Single turnover kinetic analysis of 6,7-dimethyl-8-ribityllumazine synthase.

6,7-dimethyl-8-ribityllumazine synthase (lumazine synthase) catalyzes the condensation of 5-amino-6-ribitylamino-2,4-(1H,3H)-pyrimidinedione with 3,4-dihydroxy-2-butanone 4-phosphate, affording the riboflavin precursor, 6,7-dimethyl-8-ribityllumazine. Single turnover experiments monitored by multiwavelength photometry were performed with the recombinant lumazine synthase of Bacillus subtilis. M...

Temperature-dependent presteady state kinetics of lumazine synthase from the hyperthermophilic eubacterium Aquifex aeolicus.

6,7-dimethyl-8-ribityllumazine synthase (lumazine synthase) catalyzes the condensation of 5-amino-6-ribitylamino-2,4(1H,3H)-pyrimidinedione and 3,4-dihydroxy-2-butanone 4-phosphate. Presteady state kinetic experiments using the enzyme from the hyperthermophilic bacterium Aquifex aeolicus were monitored by multiwavelength photometry. An early optical transient absorbing around 330 nm is interpre...

Catalytic Mechanism of Kdo8p Synthase. Pre-steady-state Kinetic Analysis Using Rapid Chemical Quench Flow Methods

The catalytic mechanism of 3-deoxy-D-manno-2-octulosonate-8-phosphate (Kdo8P) synthase from Escherichia coli was investigated under pre-steady-state conditions using rapid chemical quench flow methods. The results suggest the formation of acyclic bisphosphate 1 as a reaction intermediate. © 1997 Elsevier Science Ltd. 3-Deoxy-D-manno-2-octulosonate-8-phosphate (Kdo8P) synthase (EC 4.1.2.16) is a...

Kinetic Analysis of Molybdenite Oxidation