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Allostery: an illustrated definition for the 'second secret of life'.

ABSTRACT: Although allosteric regulation is the 'second secret of life', the molecular mechanisms that give rise to allostery currently elude understanding. In my opinion, experimental progress is hampered by a commonly used but misleading definition of allostery as protein structural changes that are elicited by the binding of a single ligand. Allostery is more strictly defined in functional terms as a comparison of how one ligand binds in the absence, versus the presence, of a second ligand. Therefore, as each of the two binding events involves two protein complexes, a study of allostery must consider four complexes and not just two. Such a comparison can distinguish allosteric from non-allosteric protein changes, the importance of which is frequently overlooked. When a study of all four complexes is not feasible, an alternative, albeit limited, strategy can identify subsets of allosteric-specific changes.

SUBMITTER: Fenton AW

PROVIDER: S-EPMC2574622 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature

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Allostery: an illustrated definition for the 'second secret of life'.

Fenton Aron W AW

Trends in biochemical sciences 20080815 9

Although allosteric regulation is the 'second secret of life', the molecular mechanisms that give rise to allostery currently elude understanding. In my opinion, experimental progress is hampered by a commonly used but misleading definition of allostery as protein structural changes that are elicited by the binding of a single ligand. Allostery is more strictly defined in functional terms as a comparison of how one ligand binds in the absence, versus the presence, of a second ligand. Therefore, ...[more]

PMID: 18706817

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