What did the negative control tube lack when the effect of enzyme concentration was studied. Affect H bonding enzyme structure. How Do Enzymes Speed Up Reactions Quora First the enzyme binds to the substrate and slightly distorts its shape. . The enormous catalytic activity of enzymes can perhaps best be expressed by a constant k cat that is variously referred to as the turnover rate turnover frequency or turnover numberThis constant represents the number of substrate molecules that can be converted to product by a single enzyme molecule per unit time usually. Response times may vary by subject and question complexity. In other words the enzyme reacts with the substrate forming an enzyme-substrate complex. What word describes the pH at which the speed. The shape of an enzyme is important because enzymes are shape specific. Enzymes are proteins that help increase the rate of chemical reactions inside cells. ...