Factors affecting the rate of enzyme activity

Published June 9, By Dr.

Factors affecting the rate of enzyme activity

Practically all of the numerous and complex biochemical reactions that take place in animals, plants, and microorganisms are regulated by enzymes.

These catalytic proteins are efficient and specific—that is, they accelerate the rate of one kind of chemical reaction of one type of compound,… The biological processes that occur within all living organisms are chemical reactionsand most are regulated by enzymes.

Without enzymes, many of these reactions would not take place at a perceptible rate. Enzymes catalyze all aspects of cell metabolism. This includes the digestion of food, in which large nutrient molecules such as proteinscarbohydratesand fats are broken down into smaller molecules; the conservation and transformation of chemical energy ; and the construction of cellular macromolecules from smaller precursors.

Many inherited human diseases, such as albinism and phenylketonuriaresult from a deficiency of a particular enzyme. Enzymes also have valuable industrial and medical applications.

The fermenting of wine, leavening of bread, curdling of cheeseand brewing of beer have been practiced from earliest times, but not until the 19th century were these reactions understood to be the result of the catalytic activity of enzymes. Since then, enzymes have assumed an increasing importance in industrial processes that involve organic chemical reactions.

The uses of enzymes in medicine include killing disease-causing microorganisms, promoting wound healing, and diagnosing certain diseases. Chemical nature All enzymes were once thought to be proteins, but since the s the catalytic ability of certain nucleic acids, called ribozymes or catalytic RNAshas been demonstrated, refuting this axiom.

Because so little is yet known about the enzymatic functioning of RNAthis discussion will focus primarily on protein enzymes. A large protein enzyme molecule is composed of one or more amino acid chains called polypeptide chains.

If the enzyme is subjected to changes, such as fluctuations in temperature or pH, the protein structure may lose its integrity denature and its enzymatic ability. Denaturation is sometimes, but not always, reversible.

Bound to some enzymes is an additional chemical component called a cofactorwhich is a direct participant in the catalytic event and thus is required for enzymatic activity. A cofactor may be either a coenzyme —an organic molecule, such as a vitamin —or an inorganic metal ion ; some enzymes require both.

A cofactor may be either tightly or loosely bound to the enzyme.

Factors affecting the rate of enzyme activity

If tightly connected, the cofactor is referred to as a prosthetic group. Nomenclature An enzyme will interact with only one type of substance or group of substances, called the substrateto catalyze a certain kind of reaction.

Not all enzymes have been named in this manner, however, and to ease the confusion surrounding enzyme nomenclaturea classification system has been developed based on the type of reaction the enzyme catalyzes. There are six principal categories and their reactions: Mechanism of enzyme action In most chemical reactions, an energy barrier exists that must be overcome for the reaction to occur.

This barrier prevents complex molecules such as proteins and nucleic acids from spontaneously degrading, and so is necessary for the preservation of life.

When metabolic changes are required in a cell, however, certain of these complex molecules must be broken down, and this energy barrier must be surmounted. Heat could provide the additional needed energy called activation energybut the rise in temperature would kill the cell.

The alternative is to lower the activation energy level through the use of a catalyst. This is the role that enzymes play. The unstable intermediate compound quickly breaks down to form reaction products, and the unchanged enzyme is free to react with other substrate molecules. Only a certain region of the enzyme, called the active sitebinds to the substrate.

The active site is a groove or pocket formed by the folding pattern of the protein.Diagnosis. Low grade chronic pancreatitis can be difficult to diagnose because their symptoms can be confused easily with other conditions.

Recent studies have found a high rate of under-diagnosis of chronic pancreatitis in dogs.

Factors Affecting Enzyme Activity

1 Lipase solution is best freshly made, but it will keep for a day or two in a refrigerator. Don’t try to study different temperatures on different days for the same investigation; the activity of the enzyme will change and it will not be a fair test.

Several factors affect the rate of an enzyme catalyzed reaction. Among these are enzyme concentration, substrate concentration, temperature and pH.

Besides, some molecules (activators) increase enzyme activity, while others (inhibitors) retard enzymatic activity.


Enzyme concentration: The reaction. Obesity is a condition in which a person has excess body fat. More than just a number on a scale or the size of someone's body, obesity can increase a person's risk of diseases and health problems.

Introduction to Vitamins and Minerals. Vitamins are organic molecules that function in a wide variety of capacities within the body. The most prominent function of the vitamins is to serve as cofactors (co-enzymes) for enzymatic reactions.

ReliefZyme™ Natural Factors Intensive Strength ReliefZyme is a unique enzyme blend that supports the digestive process and the breakdown of foods containing gluten, wheat, and dairy proteins.

Enzyme - Wikipedia