Question 19.4: Enzymatic Activity: Determining Optimum Temperature Consider......
Enzymatic Activity: Determining Optimum Temperature
Consider the temperature activity curve below. Enzymatic activity is shown for muscle lactate dehydrogenase from 0 °C to 60 °C. Suppose you wish to test a sample for lactate dehydrogenase activity; what is the best temperature for the test?
ANALYSIS An enzyme shows its highest catalytic activity at a certain temperature, with less activity at temperatures below and above the optimum temperature. Look at the curve of activity versus temperature and find the highest point on the curve—that point represents the optimum activity.
From the highest point on the curve of activity versus temperature, drop a vertical line down to the x-axis (the one that reads “Temperature”) to find the optimum temperature. The temperature optimum for lactate dehydrogenase is 40 °C.