Biomaterial Database

Acetate kinase from Veillonella alcalescens. Regulation by succinate and substrates. 1979

M J Griffith, and J S Nishimura

The kinetic properties of acetate kinase from Veillonella alcalescens were investigated. In the presence of high concentrations of nucleotide both forward and reverse reactions were observed. In the presence of succinate the degree of cooperativity between subunits of the homodimer decreased, i.e. the Hill coefficient, n, decreased from 2.5 to 1.4 for acetyl phosphate in the presence of succinate. At low substrate concentrations hyperbolic kinetic data were observed with succinate. We have proposed a modified version of the concerted symmetry model to describe the kinetics observed with this enzyme. The primary differentiating feature of the proposed model is the requirement for activator ligand binding for catalysis. In the absence of succinate, the substrate (acetate or acetyl phosphate) also functions as an activating ligand.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D010770	Phosphotransferases	A rather large group of enzymes comprising not only those transferring phosphate but also diphosphate, nucleotidyl residues, and others. These have also been subdivided according to the acceptor group. (From Enzyme Nomenclature, 1992) EC 2.7.	Kinases,Phosphotransferase,Phosphotransferases, ATP,Transphosphorylase,Transphosphorylases,Kinase,ATP Phosphotransferases
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D000084	Acetate Kinase	An enzyme that catalyzes reversibly the phosphorylation of acetate in the presence of a divalent cation and ATP with the formation of acetylphosphate and ADP. It is important in the glycolysis process. EC 2.7.2.1.	Acetokinase,Kinase, Acetate
D000085	Acetates	Derivatives of ACETIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxymethane structure.	Acetate,Acetic Acid Esters,Acetic Acids,Acids, Acetic,Esters, Acetic Acid
D000494	Allosteric Regulation	The modification of the reactivity of ENZYMES by the binding of effectors to sites (ALLOSTERIC SITES) on the enzymes other than the substrate BINDING SITES.	Regulation, Allosteric,Allosteric Regulations,Regulations, Allosteric
D001667	Binding, Competitive	The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.	Competitive Binding
D013386	Succinates	Derivatives of SUCCINIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain a 1,4-carboxy terminated aliphatic structure.	Succinic Acids,Acids, Succinic
D014678	Veillonella	A genus of gram-negative, anaerobic cocci parasitic in the mouth and in the intestinal and respiratory tracts of man and other animals.