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Amylase is an important metabolic enzyme. Its function is to catalyze the hydrolysis of starch into glucose. This particular enzyme, which is found in all mammals, speeds up specific digestive processes which take place along the digestive track running from the mouth to the small intestines. Amylase's essential role in digestion makes it an attractive prospect for research.

The human body must be kept within several degrees of 37° Celsius for biological functions to continue working. If body heat exceeds 37°C by too much cells become impaired or permanently damaged, at lower temperature metabolism decreases without permanent damage until ice crystals form in the cells. What happens to Amylase at extreme temperatures? Perhaps the answer to that question will give insight into metabolism's reaction to low temperatures.

There are over 700 enzymes which have currently been identified. An enzyme is defined as a catalyst which increases the rate of a metabolic reaction. Most enzymes are specific, meaning that they only work on a particular reaction or class of reactions. Many industrial processes make use of enzymes to create their products. Yogurt, cheese, sauerkraut, and cottage cheese are just a few of the many products enzymes are used to make.

Denaturing is defined as a major change from the native state to another state without changing the primary structure. Enzyme denaturation usually leaves the enzyme without its catalytic functions. There are three factors which can denature an enzyme: temperature, pH, and ion concentration.

Amylase does not become denatured at extreme cold (approx. 0°C) nor at room temperature (approx. 25°C). However, at an elevated temperature of approximately 100°C amylase does become denatured. When substances are exposed to high heats the atoms bounce more quickly and hit each other with greater force than they do at lower temperatures. High temperature often causes irreversible damage to the molecular structure of enzymes due to the velocity with which the atoms move about. Low temperatures by themselves do not appear to cause damage to enzymes.

One controversy which is currently present over heat denaturation on enzymes is the heat-shock theory. Paul Benson and Mark Brodl from Knox college conducted an experiment where alpha-amylase was exposed to progressively higher temperatures over the course of a couple days and the enzyme was not denatured. This could be interpreted in the fact that the molecules habituate to the fast moving atoms when the temperature is raised slowly and are not damaged.

In nature, extreme low temperatures often occur due to climate, yet extreme hot temperatures aren't prevalent. It is possible that enzymes can not withstand extreme high temperatures because they did not evolve to do so. Perhaps amylase evolved to handle low temperatures because those who did not were denatured thus never passing on their characteristics.

Cold temperature is similar to what cold blooded animals face in winter every year. The amylase cells which could not handle the cold died. Conversely the boiling presented conditions which amylase was not prepared to deal with. that the enzyme is denatured at high temperatures. Denatured amylase no longer catalyzes the hydrolysis of starch into glucose.