Enzymes are biological catalysts. Catalysts lower the activation energy for reactions. The lower the activation energy for a reaction, the faster the rate. Thus enzymes speed up reactions by lowering activation energy.

They live in soil, water and hot springs. A spring which is synthesized from the appearance of geothermally heated ground water from the earth’s crust is known as hot spring. Bacteria which live in hot springs are metabolically active because of the bacteria have high optimal temperatures.

Chapter 3 – Chemistry in Industrial Instrumentation. A chemical reaction resulting in a net release of energy is called exothermic. Conversely, a chemical reaction requiring a net input of energy to occur is called endothermic.

If all of the enzymes in the system bind to the substrate, the additional substrate molecules must wait for the enzyme to become available after the reaction is complete. This means that as the enzyme concentration decreases, the reaction rate will decrease.

Enzymes lower the activation energy of a reaction – that is the required amount of energy needed for a reaction to occur. They do this by binding to a substrate and holding it in a way that allows the reaction to happen more efficiently.

about 98.6 degrees Fahrenheit

The shape of an enzyme also depends on its temperature. When enzymes get too warm, they get too loose. When the temperature is too hot, too cold, or unsteady, the enzymes will spend less time in their optimal shape which simply translates into having a less than optimal metabolism.

Lowering the temperature slows the motion of molecules and atoms, meaning this flexibility is reduced or lost. Each enzyme has its zone of comfort, or optimal temperature range, within which it works best. As the temperature decreases, so does enzyme activity.

Importantly, the levels at which enzymes can catalyze their target reactions and the ability of enzymes to maintain their structure are highly dependent on temperature. As a result, freezing and boiling can have significant effects on enzyme activity. Boiling breaks down enzymes so they no longer work.

Freezing is a physical process involving the transformation of water molecules from an amorphous state to highly structured ice crystals. The phase change can lead to protein denaturation caused by alterations in the chemical and physical environment of the protein.

For long term storage (more than a week), it becomes necessary to freeze the protein preparation. It is important to freeze it rapidly using liquid nitrogen or a dry ice/ethanol mixture to avoid denaturation. At this temperature it is necessary to add 50% glycerol to the solution to avoid freezing.

The course of protein degradation at 42°C differs from those at 28°C and 35°C by the absence of the second phase of degradation (Fig. 1B). Sporulation is also suppressed at this temperature. However, the amount of the “labile” protein fraction and its degra- dation constant kl are increased.

If a protein loses its shape, it ceases to perform that function. The process that causes a protein to lose its shape is known as denaturation. Denaturation is usually caused by external stress on the protein, such as solvents, inorganic salts, exposure to acids or bases, and by heat.

When food is cooked, some of its proteins become denatured. This is why boiled eggs become hard and cooked meat becomes firm. A classic example of denaturing in proteins comes from egg whites, which are typically largely egg albumins in water. The same transformation can be effected with a denaturing chemical.