Question

Using aspartate transcarbamoylase as an example, explain how the structure of allosteric enzymes shift on binding to allosteric inhibitors

Answer 1

Direct control of protein function via allosteric regulation is usually achieved through conformational changes of a given protein structure induced by effectors. In contrast to intrasteric regulation effectors bind to regulatory sites distinct from the active site (Greek, allos = other, stereos = rigid, solid, or space). One term tightly linked to allostery is “cooperativity.” This describes the interaction of binding processes of ligands to proteins with multiple binding sitesLigand binding plots of positively cooperative systems generally display sigmoidicity, resulting in an S-shaped curve of fractional saturation or rate against concentration. Allosteric behavior itself was often observed for regulatory or control enzymes of metabolic pathways and forms the basis for feedback inhibition and activation.