Question

If an enzyme-mediated reaction were carried out at a temperature that was higher or lower than optimal, the vmax for the reaction would probably be

Answer 1

Answer;

-The vmax for the reaction would probably be decreased.

Explanation;

- Vmax is the rate of reaction when the enzyme is saturated with substrate is the maximum rate of reaction. The relationship between rate of reaction and concentration of substrate depends on the affinity of the enzyme for its substrate.

-Km is the concentration of substrate which permits the enzyme to achieve half Vmax. An enzyme with a high Km has a low affinity for its substrate, and requires a greater concentration of substrate to achieve Vmax.

-The velocity of enzyme reaction increases when temperature of the medium is increased; reaches a maximum and then falls (Bell shaped curve). The temperature at which maximum amount of the substrate is converted to the product per unit time is called the optimum temperature. Temperature is increased, more molecules get activation energy, or molecules are at increased rate of motion. Their collision probabilities are increased and so the reaction velocity is enhanced.

Answer 2

Answer:

The vmax would be decreased.

Explanation:

Since enzymes are also proteins, factors such as pH, temperature and substrate concentration will influence their performance. Enzymes, like all proteins, are denatured under certain conditions and stop working, or have the Vmax of their reactions diminished.

Thus, the vmax of an enzymatic reaction increases to some extent with increasing temperature. From a certain optimum temperature (whose value depends on the enzyme that is reacting), where the reaction speed is maximum, protein denaturation occurs, which inactivates the enzyme. This is because there is a change in its three-dimensional shape, so the enzyme can no longer attach to the substrate and catalyze the chemical reaction. Thus, after passing the optimum temperature, the reaction Vmax decelerates rapidly.