An entropic mechanism of generating selective ion binding in macromolecules.

ABSTRACT: Several mechanisms have been proposed to explain how ion channels and transporters distinguish between similar ions, a process crucial for maintaining proper cell function. Of these, three can be broadly classed as mechanisms involving specific positional constraints on the ion coordinating ligands which arise through: a "rigid cavity", a 'strained cavity' and 'reduced ligand fluctuations'. Each operates in subtly different ways yet can produce markedly different influences on ion selectivity. Here we expand upon preliminary investigations into the reduced ligand fluctuation mechanism of ion selectivity by simulating how a series of model systems respond to a decrease in ligand thermal fluctuations while simultaneously maintaining optimal ion-ligand binding distances. Simple abstract-ligan

SUBMITTER: Thomas M 

PROVIDER: S-EPMC3585399 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature