Activation of acyl condensation reaction of monomeric 6-Hydroxymellein (cas 19314-92-2) synthase, a multifunctional polyketide biosynthetic enzyme, by free coenzyme A

Add time:08/10/2019    Source:sciencedirect.com

6-Hydroxymellein (cas 19314-92-2) (6HM) synthase is a multifunctional polyketide enzyme induced in carrot cells, whose fully active homodimer catalyzes condensation of acyl-CoAs and the NADPH-dependent ketoreduction of the enzyme-bound intermediate. 6HM-forming activity of the synthase was markedly decreased when the reaction mixture pH was adjusted from 7.5 to 6.0. However, under these slightly acidic conditions, the acyl condensation catalyzed by the dissociated monomer enzyme was appreciably stimulated by addition of free coenzyme A (CoA). In contrast, the condensation reaction at pH 6.0 was significantly inhibited in the presence of CoA when the reaction was carried out with the NADPH-omitted dimer synthase. Among the kinetic parameters of the acyl condensation, velocity of the monomer-catalyzing reaction at the acidic pH was appreciably increased upon addition of CoA while Kms did not show any significant change in the presence and absence of the compound. These results suggest that CoA associates with a specific site in the dissociated monomeric form of 6HM synthase, and the velocity of the acyl condensation reaction catalyzed by the CoA-synthase complex appreciably increases in acidic conditions.

We also recommend Trading Suppliers and Manufacturers of 6-Hydroxymellein (cas 19314-92-2). Pls Click Website Link as below: cas 19314-92-2 suppliers

Prev:Role of reducing co-factors in catalytic reactions of 6-Hydroxymellein (cas 19314-92-2) synthase, a multifunctional polyketide biosynthetic enzyme in carrot cells
Next:Free CoA as activator of 6-Hydroxymellein (cas 19314-92-2) synthase, a multifunctional polyketide biosynthetic enzyme in carrot)