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Enzyme productivity

LuisanaT's picture


Introduction

Enzymes are found within all living organisms, facilitating chemical reactions for things to either fall apart or come together. These enzymes are in constant random motion, eventually coming into contact with other molecules that compliment perfectly with their specific shape, called substrates. They react with one another as a result, allowing their combined product to come into existence naturally. Now if we consider speed in this equation, the slower the enzymes move, the longer it will take for them to find and therefore interact with the appropriate substrate. Conversely, the faster the random motion the enzymes are exhibiting, the shorter the amount of time it should take for the reaction to run to completion.

But this increased velocity may result in too hard of a collision between the molecule and the enzyme and damage the specific shape of either individual, preventing them from interacting properly with their predetermined partner. Another possibility is that the change in temperature will cause the enzymes to react with one another instead of the substrates. For a change in temperature can lead to the enzymes fusing together, filling in and therefore eliminating their specific shape and disabling it completely. But on the other hand, this may produce a double headed enzyme, so to speak, causing the reaction time to occur twice as fast. Whatever the case may be, our group decided to hypothesize that the rate at which the end result will be achieved will increase with additional heat.

Method:

In going about with this hypothesis of ours, we explored the break down of the substrate hydrogen peroxide into water and oxygen with the aid of the enzyme hydrogen peroxidase:

2H2O2 ---> 2H2O + 02

Just in the similarity of the names alone we can see that there is a special relationship between the two molecules. To test our claim, we decided to compare the time it takes in seconds for this process to take place in environments of three different temperatures: chilled, room, and hot. The rate at which the reaction is completed has been defined by the rising of a small filter disc saturated with the hydrogen peroxidase to the surface of a hydrogen peroxide solution in a fifty milliliter beaker.

Observation:

After four trials under average room temperature, the time it took for the enzymes to break down the hydrogen peroxide was an average of approximately 6.5 seconds. Differently, when the trial was done under higher temperatures, an entire minute and a half passed without any change in the positioning of the filter disc in the beaker. This same result occurs after the passing of a generous five minutes when the enzymes and substrates come into contact with one another under low temperatures.

Results:

By altering the temperature of the environment, the enzyme’s ability to work normally is in fact affected. An enzyme at a temperature outside of room temperature is unable to serve its original function properly, meaning that room temperature is closest to this enzyme’s ideal environment. Based on this, both chilled and hot environments are extreme temperatures for the enzymes, rendering a large enough change in heat to limit their productivity. This altogether implies that the preservation of a particular temperature is crucial for a reaction to run to completion.

Discussion

But why are there so many limitations on enzyme productivity? Both enzymes and substrate already have highly specific conditions to be met before they are able to react and introducing the concept of the temperature of the environment only makes it more difficult to achieve. There must therefore be an utmost importance in the location of the end result produced from the reaction. If the reactants involved in the chemical equation can not undergo their usual behavior, react effectively with one another, in a given area, then it is just as probable that the end product will not function properly there either. This renders temperature as a great regulatory mechanism for where and even when the product can exist. If enzymes are in fact constantly moving around, they can randomly arrive to a region different from their designated one not only in the function it serves to entire the organism but also in temperature. It would be unnecessary for them to react and form their specific product here in the same way that it would be unnecessary for all of the different types of enzymes to produce all of their different products in the same place that is specialized for the utilization of only certain things.