Inhibitor functional active site figure 820

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: ts active site no longer functions. Noncompetitive inhibitor Figure 8.19 (c) Noncompetitive inhibition • Concept 8.5: Regulation of enzyme activity helps control metabolism • A cell’s metabolic pathways • Must be tightly regulated Allosteric Regulation of Enzymes Allosteric • Allosteric regulation • Is the term used to describe any case in which a protein’s function at one site is affected by binding of a regulatory molecule at another site • Non­competitive inhibition is a form of allosteric regulation • They change shape when regulatory molecules bind to specific sites, affecting function Allosteric activater Allosteric enyzme with four subunits Regulatory site (one of four) Active site stabilizes active from (one of four) Activator Active form Stabilized active form Oscillation Allosteric activater stabilizes active form NonInactive form Inhibitor functional active site Figure 8.20 Stabilized inactive form (a) Allosteric activators and inhibitors. In the cell, activators and inhibitors dissociate when at low concentrations. The enzyme can then oscillate again. • Cooperativity • Is a form of allosteric regulation that can amplify enzyme activity Binding of one substrate molecule to active site of one subunit locks all subunits in active conformation. Substrate Inactive form Figure 8.20 Stabilized active form (b) Cooperativity: another type of allosteric activation. Note that the inactive form shown on the left...
View Full Document

This note was uploaded on 11/09/2011 for the course BIO 181 taught by Professor Staff during the Summer '10 term at Chandler-Gilbert Community College.

Ask a homework question - tutors are online