Biomaterial Database

Chorismate mutase-prephenate dehydratase from Escherichia coli: active sites of a bifunctional enzyme. 1978

R G Duggleby, and M K Sneddon, and J F Morrison

The relationship between the active sites of the bifunctional enzyme chorismate mutase-prephenate dehydratase has been examined. Steady-state kinetic investigations of the reactions with chorismate or prephenate as substrate and studies of the overall conversion of chorismate to phenylpyruvate indicate that there are two distinct active sites. One site is responsible for the mutase activity and the other for the dehydratase activity. Studies of the overall reaction using radioactive chorismate show that prephenate, which is formed from chorismate, dissociates from the mutase site and equilibrates with the bulk medium before combining at the dehydratase site. No evidence was obtained for direct channeling of prephenate from one site to the other, or for any strong interaction between the sites.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008956	Models, Chemical	Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.	Chemical Models,Chemical Model,Model, Chemical
D011302	Prephenate Dehydratase	An enzyme that catalyzes the conversion of prephenate to phenylpyruvate with the elimination of water and carbon dioxide. In the enteric bacteria this enzyme also possesses chorismate mutase activity, thereby catalyzing the first two steps in the biosynthesis of phenylalanine. EC 4.2.1.51.	Chorismate Mutase-Prephenate Dehydratase,Prephenate Hydro-lyase,Chorismate Mutase Prephenate Dehydratase,Dehydratase, Chorismate Mutase-Prephenate,Dehydratase, Prephenate,Hydro-lyase, Prephenate,Mutase-Prephenate Dehydratase, Chorismate,Prephenate Hydro lyase
D002384	Catalysis	The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.	Catalyses
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D006836	Hydro-Lyases	Enzymes that catalyze the breakage of a carbon-oxygen bond leading to unsaturated products via the removal of water. EC 4.2.1.	Dehydratase,Dehydratases,Hydrase,Hydrases,Hydro Lyase,Hydro-Lyase,Hydro Lyases,Lyase, Hydro,Lyases, Hydro
D001665	Binding Sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.	Combining Site,Binding Site,Combining Sites,Site, Binding,Site, Combining,Sites, Binding,Sites, Combining