al·lo·ster·ism

, allostery (ă-los'ter-izm, -los'ter-ē),

The influencing of an enzyme activity, or the binding of a ligand to a protein, by a change in the conformation of the protein, brought about by the binding of a substrate or other effector at a site (allosteric site) other than the active site of the protein. Compare: cooperativity, hysteresis.

Farlex Partner Medical Dictionary © Farlex 2012

allostery

A phenomenon in which a ligand binds to a specific receptor site on a protein, changing its shape, and altering the affinity for a ligand at a second site (e.g., either a receptor or a binding site); the ability of an effector molecule (ligand) to change the conformation and activity of a protein.

In allostery, the catalytic function of an enzyme may be modified by interaction with small molecules, not only at the active site but also at a spatially distinct (allosteric) site of different specificity. Allostery refers to an interaction of two or more functional sites on a protein, or two or more proteins, resulting in altered affinity of ligand binding; it depends on dynamic interaction with a substrate or other molecule—e.g., heme-heme interaction.

al·lo·ster·ism

, allostery (al'ō-ster'izm, al'ō-ster'ē)

Medical Dictionary for the Health Professions and Nursing © Farlex 2012

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References in periodicals archive

Karplus, 2008, "Allostery and Cooperativity Revisited", Protein Science, vol.

CONCEPTUAL RECONSTRUCTION AND EPISTEMIC IMPORT: ALLOSTERIC MECHANISTIC EXPLANATIONS AS A UNIFIED THEORY-NET

"We are looking at several problems, such as drug discovery, protein analysis, allostery and virus particles," he says.

EAR spectroscopy assesses proteins' good vibrations

In the present study allostery was revealed in the protein kinase A catalysed reaction of peptide phosphorylation, and the effect was quantified in terms of the interaction factor [alpha] for seven substrates.

The understanding of the term 'allostery' has been significantly widened during some recent years, and today this phenomenon can be defined as the coupling of binding properties of two separate ligand binding sites, independently whether the sites are located on the oligomeric or monomeric protein molecule [4].

Considering this trend the principle 'better binding: stronger allostery' was formulated for protein kinase A catalysis.

Proceeding from this analogy, we were able to quantify the principle 'better binding: stronger allostery' in terms of the LFE relationship, as defined by Eq.

Single-subunit allostery in the kinetics of peptide phosphorylation by protein kinase A/proteiinkinaasi a kataluutilise alauhiku allosteeria ilmnemine peptudide fosforuleerimise kineetikas

They discuss structural characterization of EPAC by x-ray crystallography; sensory neuron cAMP signaling in chronic pain; monitoring real-time cyclic nucleotide dynamics in subcellular microdomains; identifying complexes of adenylyl with A-kinase anchoring proteins; assessing cyclic nucleotide binding domain allostery and dynamics by nuclear magnetic resonance spectroscopy; a protocol for expression and purification of cyclic nucleotide-free protein in E.

Cyclic Nucleotide Signaling