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8 factors that affect enzymatic activity

The Factors Affecting Enzymatic Activity are these agents or conditions that can alter the function of enzymes. Enzymes are a class of proteins whose function is to speed up biochemical reactions. These biomolecules are essential for all life forms, plants, fungi, bacteria, protists and animals.

Enzymes are essential for various important reactions of organisms, such as the elimination of toxic compounds, the breakdown of food and the production of energy.

Enzymes are like molecular machines that facilitate the tasks of cells, and in many cases their function is influenced or favored under certain conditions.

List of factors that affect enzymatic activity

Enzyme concentration

As the concentration of enzymes increases, the rate of reaction increases proportionally. However, this only applies up to a certain concentration, because at a certain moment the speed becomes constant.

This property is used to determine the activities of serum enzymes (blood serum) for diagnosing disease.

Substrate concentration

Increasing the substrate concentration increases the rate of the reaction. This is because more substrate molecules collide with the enzyme molecules, so the product forms faster.

However, if a certain substrate concentration is exceeded, this has no effect on the reaction speed, since the enzymes are saturated and work at their maximum speed.


Changes in the concentration of hydrogen ions (pH) significantly affect the activity of enzymes. Because these ions are charged, they create forces of attraction and repulsion between the hydrogen and ionic bonds of the enzymes. This interference leads to changes in the shape of the enzymes and thus affects their activity.

Every enzyme has an optimal pH value at which the reaction rate is at its maximum. Therefore, the optimal pH for an enzyme depends on where it normally works.

For example, intestinal enzymes have an optimal pH of around 7.5 (slightly basic). In contrast, enzymes in the stomach have an optimal pH of around 2 (very acidic).


The concentration of salts also influences the ion potential and consequently they can intervene in certain compounds of the enzymes, which can be part of the active center thereof. In these cases, as with pH, ​​the enzymatic activity is affected.


As the temperature increases, the enzymatic activity increases and, consequently, the speed of the reaction. However, very high temperatures denature the enzymes, which means that the excess energy breaks the bonds that maintain their structure so that they do not function optimally.

Therefore, the rate of the reaction decreases rapidly as the thermal energy denatures the enzymes. This effect can be observed graphically in a bell-shaped curve, where the reaction rate is related to the temperature.

The temperature at which the maximum rate of reaction occurs is called the optimal temperature of the enzyme, which is observed at the highest point of the curve.

This value is different for the different enzymes. However, most of the enzymes in the human body have an optimal temperature of around 37.0 ° C.

In summary, as the temperature increases, the reaction rate will initially increase due to the increase in kinetic energy. However, the effect of the disconnection will increase and the response speed will decrease.

Concentration of the product

The accumulation of the reaction products generally reduces the rate of the enzyme. In some enzymes, the products combine with their active site to form a loose complex and therefore inhibit the activity of the enzyme.

In living systems, this type of inhibition is usually prevented by rapidly eliminating the products formed.

Enzymatic activators

Some of the enzymes require the presence of other elements in order to function better, these can be inorganic metal cations like Mg2+Mn2+Zn2+Approx2+, Co2+Cu2+, N / A+, K+etc.

In rare cases, anions are also required for enzymatic activity, for example: chloride anion (CI-) for amylase. These tiny ions are called enzyme cofactors.

There is also another group of elements that favor the activity of enzymes called coenzymes. Coenzymes are organic molecules that contain carbon, like the vitamins in food.

An example would be vitamin B12, which is the coenzyme of methionine synthase, an enzyme that is necessary for the metabolism of proteins in the body.

Enzyme inhibitors

Enzyme inhibitors are substances that negatively affect the function of enzymes and thus slow down or in some cases stop catalysis.

There are three common types of enzyme inhibition: competitive, non-competitive, and substrate inhibition:

Competition inhibitors

A competitive inhibitor is a chemical compound similar to a substrate that can react with the active site of the enzyme. If the active site of an enzyme has been bound to a competitive inhibitor, the substrate cannot bind to the enzyme.

Non-competitive inhibitors

A non-competitive inhibitor is also a chemical compound that binds to another site in the active site of an enzyme, an allosteric site. As a result, the enzyme changes shape and can no longer easily bind to its substrate, so that the enzyme cannot function properly.


  1. Alter, S. (2000). Biology: understanding life (3rd edition). Jones and Bartlett learn.
  2. Berg, J., Tymoczko, J., Gatto, G. & Strayer, L. (2015). biochemistry (8th edition). W. H. Freeman and Company.
  3. Russell, P.; Wolfe, S .; Hertz, P .; Starr, C. & McMillan, B. (2007). Biology: The Dynamic Science (1st edition). Thomson Brooks / Cole.
  4. Seager, S .; Slabaugh, M & Hansen, M. (2016). Chemistry for Today: General, Organic, and Biochemistry (9th edition). Cengage learning
  5. Stoker, H. (2013). Organic and biological chemistry (6th edition). Learn Brooks / Cole Cengage.
  6. Voet, D., Voet, J. and Pratt, C. (2016). Basics of Biochemistry: Living on Molecular level (5th edition). Wiley