Unexpected Enviromental factors On Enzyme Activity?

[bjon-07]

Hi all,

I am currently a college frosh taking cellular biology lab. In lab we did an experminet to measure how tempature effects enzyme activity. We put 1 mL of B-galactosidase (when a certain substrate is added to this enzyme, a yellow liquid (product) is formed). Then we use a Spec-20 to measure the absorbance of light at 420 nm, thus we can measure the rate of the reaction).

I know that a graph of enzyme activity (rate) vs. temperature should produces an upside down possion distributin ( or a funky "U" shape) This beacasue enzymes have a peak tempature at which they work best at.


On my graph, the curve contains two peaks, one at 37 degree (body temp) and the other at 60 degrees.

Can an enzyme have two peak levels of effcintcy. It does make sense to me. I thought that the rate at which enzymes process substrate increase with temaperature until the tempature is high enough to denature the enzyme rendering it inactive.

Thank your the help, it is greatly apperated

 

[nautica]

At that temp,the enzyme should be denatured and completely useless. Could something else have caused the peak?

Nautica

 

[ravenprp]

Hi there,

That's a great question! It is true that enzymes have an optimal temperature at which they work best, and this is usually around body temperature (37 degrees Celsius). However, there are some unexpected environmental factors that can affect enzyme activity, and temperature is just one of them.

Other factors such as pH, substrate concentration, and the presence of inhibitors or activators can also have a significant impact on enzyme activity. In your experiment, it is possible that the presence of certain compounds or ions in the enzyme solution may have affected the enzyme's efficiency at different temperatures, resulting in the two peaks on your graph.

Additionally, some enzymes are known to have multiple forms or isoforms, each with slightly different optimal temperatures. This could also explain the two peaks on your graph.

It is important to keep in mind that enzymes are complex biological molecules and their activity can be influenced by a variety of factors. It is always a good idea to repeat experiments and analyze the results to confirm any unexpected findings.

I hope this helps to answer your question and good luck with your studies!