Structural enzymological studies of multifunctional enzyme, type-1 (MFE1) with the 2E-decenoyl-CoA and 2E,4E-decadienoyl-CoA substrates: The regeneration of the dehydrogenase catalytic site is the rate limiting step of its combined reactions.

-values of the overall reaction of the studied substrates, concerns the regeneration of the HAD active site, after the dehydrogenation step. It is discussed that this kinetic behavior could be related to the dynamical properties of the enzyme. The crystallographic binding studies of RnMFE1 with 2E,4E-decadienoyl-CoA have captured its mode of binding in the ECH active site as a competent enzyme product complex but also as an incompetent enzyme substrate complex. Structural analysis shows that positively charged patches on the enzyme surface between the ECH and HAD active sites would facilitate the channeling of the hydrated intermediate of 2E,4E-decadienoyl-CoA between these sites by electrostatic steering, without being released into the bulk solvent.