Five Years from Now What You Want to Do

Enzyme Study Questions 1. Definitions/terminology: o enzyme: a protein molecule that catalyzes chemical reactions without itself being destroyed or altered o catalyst: a substance that increases the rate of a chemical reaction but is not consumed or changed by it. o substrate: a substance upon which the enzyme acts. o denaturation: the partial or total alteration of the structure of a protein without change in covalent structure by the action of certain physical procedures (heating, agitation) or chemical agents. Any disruption of the protein structure that is accompanied by a loss of activity o cofactor: nonprotein molecules that must bind to a particular enzyme before a reaction occurs (natural reactant – usually a metal ion or a coenzyme) o coenzyme: a diffusible, heat-stable substance of low molecular weight that when combined with an inactive protein called an apoenzyme forms an active compound or a complete enzyme called a holoenzyme o apoenzyme: the protein part of an enzyme o prostheticgroup: the coenzyme bound tightly to the enzyme o holoenzyme: the functional compound formed by the combination of an apoenzyme and its appropriate coenzyme o zymogen: Some enzymes, mostly digestive enzymes, are originally secreted from the organ of production in a structurally inactive form o activation energy: the energy required for a molecule to form an activated complex; in an enzyme-catalyzed reaction, corresponds to the formation of the activated enzyme substrate complex o enzyme-substrate complex (E-S): a molecule of substrate is bound to the active center of the enzyme molecule o active site: where the initial binding of substrate and enzyme occurs o absolute specificity: meaning that the enzyme combines with only one substrate and catalyzes only the one corresponding reaction o group specificity: they combine with