Monod-Wyman-Changeux model

Glycogen phosphorylase conforms to the Monod-Wyman-Changeux model of allosteric transitions, with the active form of the enzyme designated the R state and the inactive form denoted as the T state (Figure 15.17). Thus, AMP promotes the conversion to the active R state, whereas ATP, glucose-6-P, and caffeine favor conversion to the inactive T state. 

In the Monod-Wyman-Changeux model for allosteric regulation, what values of L and relative affinities of R and T for A will lead activator A to exhibit positive homotropic effects (That is, under what conditions will the binding of A enhance further A-binding, in the same manner that S-binding shows positive coop-... 

Linked-function mechanisms for cooperative binding interaction of metabolites and/or drugs, based on the presence of two or more different conformational states of the protein or receptor. See Adair Equation Cooperative Ligand Binding Hemoglobin Hill Equation Plot Koshland-Nemethy-Filmer Model Monod-Wyman-Changeux Model Negative Cooperativity Positive Cooperativity... 

A graphical procedure used to determine, in cooperative systems, values for L (the ratio of the T to R state in the absence of any binding ligand in the Monod-Wyman-Changeux model) and n (the stoichiometry of binding) in exclusive binding systems (c = 0 where c = i.e., the ratio of the intrinsic dissociation constants for... 

A subset in allosteric models of cooperativity. If an allosteric effector, upon binding to a cooperative enzyme, alters the Michaelis or dissociation constants (or [S0.5] value) for the substrate(s) (but not the h"max values), then that protein is a A system enzyme. See Monod-Wyman-Changeux Model K. E. Meet (1980) Meth. Enzymol. 64, 139. 

It should also be noted that the common models of allosterism (e.g., the Monod-Wyman-Changeux model and the Koshland-Nemethy-Filmer model) assume rapid equilibrium binding. 

MICHAELIS-MENTEN EQUATION MICHAELIS-MENTEN KINETICS MONOD-WYMAN-CHANGEUX MODEL NEGATIVE COOPERATIVITY POSITIVE COOPERATIVITY Cooperativity index. 

MONOD-WYMAN-CHANGEUX MODEL COORDINATE-COVALENT BOND COORDINATION NUCLEARITY... 

STEREOCHEMICAL TERMINOLOGY, lUPAC RECOMMENDATIONS HETEROTROPIC EFFECT MONOD-WYMAN-CHANGEUX MODEL HEMOGLOBIN ALLOSTERISM... 

COOPERATIVITY ALLOSTERISM INDUCED FIT MODEL MONOD-WYMAN-CHANGEUX MODEL INDEPENDENT BINDING LINKED FUNCTIONS ADAIR EQUATION POSITIVE COOPERATIVITY NEGATIVE COOPERATIVITY KOSMOTROPES CHAOTROPIC AGENTS HOFMEISTER SERIES Kp, Kq, K .. . ... 

MONOD-WYMAN-CHANGEUX MODEL Ligand binding sites,... 

MONOD-WYMAN-CHANGEUX MODEL MONOGLYCERIDE LIPASE MONO-ISO MECHANISMS... 

EXPONENTIAL BREAKDOWN SYMBOLIC COMPUTING Symmetry-conserving allosteric model, MONOD-WYMAN-CHANGEUX MODEL SYMPORT Symproportionation,... 

The mammalian (largely rabbit) muscle enzyme has been the most investigated X-ray structural work favours a GTB fold. It has control, covalent and allosteric, at several levels and these are usually discussed in terms of a modification of the Monod-Wyman-Changeux model, in which the individual polypeptide monomers can adopt either a non-catalytic T ( tense ) state or a catalytic R ( relaxed ) state, but mixed oligomers (e.g. TR in a dimer) do not occur. In the extensive structural studies, oligomers with mixed conformations have never been observed. 

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