Khan academy 2

Regulatory molecules

Activators and inhibitors

Activators

Molecules that increase the activity of an enzyme

Inhibitors

Molecules that decrease the activity of an enzyme

Activator and inhibitor binding length

Reversible

Competitive inhibition

Inhibitor binds to an enzyme and blocks binding of a substrate

Noncompetitive inhibition

Inhibitor attaches at other site of enzyme and prevents it from doing its job

Competitive inhibitor traits

Can be out-competed by lots of substrates and reach maximum rate

Noncompetitive inhibitor traits

Enzyme-catalyzed reaction will never reach normal maximum rate

Allosteric regulation

Regulatory molecule binds to an enzyme some place other than the active site

Allosteric site

Place where regulatory molecules bind to an enzyme other than active site

Allosteric enzymes

Special enzymes that have an allosteric site along with an active site

Allosteric inhibitor impact on allosteric enzymes

All active sites are charged slightly, working less well

Cooperatively

Substrate serves as an allosteric activator, increasing other active sites activity when minded

Cofactors

Non-protein molecules that assist enzymes in carrying out chemical reactions

Coenzymes

Cofactors that are organic molecules

Feedback inhibition

The product of a metabolic pathway binds to an allosteric site of the beginning enzyme, stopping production

First committed step

A first step that’s irreversible