Enzyme Temperature Lab Report

I) Introduction

This lab was designed to test what effect multiple temperatures would have on the activity of an enzyme. It’s scientifically known that there’s a positive correlation between temperature and an enzyme’s rate of reaction. In other words, as temperature increases, so too does the rate of reaction of an enzyme. However, this correlation between temperature and enzyme activity doesn’t stay positive indefinitely. In fact, as temperature increases, it will eventually hit a certain point known as the optimal temperature. It’s at this temperature where enzyme activity is at its highest. If this temperature is exceeded, it will result in the enzyme losing its ability to function, thereby causing a drop-off in that particular enzyme’s

In addition to the test tubes, substances known as Reaction Buffer A and B, ONPG, and the enzyme β-gal were collected for use. A serological pipette with a pump was used so that the substances could be properly dispensed into the test tubes. In order to thoroughly mix these substances together inside the test tubes, a vortex mixer was used throughout the experiment. A timer was also used, because timing was a critical factor in this experiment. Other major pieces of equipment, called water baths, were also used. These baths allowed for varying levels of temperature incubation, and were setup in different locations of the room where the experiment took place. Finally, a spectrophotometer was also employed so that absorbance readings could be gathered. These absorbance readings were extremely important because without them, it would have been very difficult to determine if there was an increase or decrease in the enzyme’s rate of reaction. All but one of these materials were constant conditions. This other material, which was the water baths, was the independent

Remember, a vortex mixer was used for all mixing in this experiment in order to ensure thorough substance combination. Also, six separate groups conducted the same experiment, and pooled their data together to collect a mean absorbance for each test tube number. For instance, the first test tube for each group had a calculated mean. This meant that there would be a result of six separate averages, one for each test tube group. To begin the experiment, 2 mL of Buffer A and 500 µL of ONPG were pipetted into each test tube, then mixed together. This next step, which required precise timing, was crucial. Firstly, 500 µL of the enzyme, β-gal, was pipetted into the first test tube. Immediately after the enzyme was placed into the test tube, a ten minute timer was started. That test tube was then placed on the vortex. Again, timing was crucial. So after the test tube finished mixing, fifteen seconds was counted down. After those fifteen seconds elapsed, the second test tube, which already had 500 µL of β-gal pipetted into it, was immediately mixed on the vortex. This process continued on until the sixth test tube was done. The seventh test tube, or the blank, underwent the same process except for one difference. Instead of containing the enzyme, the blank had a 500 µL of Buffer A pipetted into it. This was done to create equal levels of volume in all seven test tubes, thereby eliminating any volume