Catalysis of Enzymes

In order to carry out various life activities, the organism must obtain energy and produce new substances needed for its growth. By ingesting nutrients, organisms produce energy through decomposition; or produce new substances through synthesis. In organisms, nutrition molecules participate in various decomposition and synthesis reactions, collectively known as metabolism.

Any substance has more or less energy. When a substance changes through a chemical reaction, it will take a long time to complete under the condition of no external force. This long-term reaction is not enough to maintain life activity of the organism. Therefore, organisms have developed a set of metabolic pathways that can quickly generate energy and synthesize new substances, that is, each metabolic reaction pathway needs the help of "enzymes" in order to complete it quickly. Enzyme is a protein that catalyzes the reaction. Because each enzyme molecule has its special structure, each enzyme can only catalyze specific substrates. This enzyme's specificity for receptors is much like the relationship between a lock and a key. Enzymes are usually named according to their specificity for receptors. For example, enzymes that break down starch are called amylase.

Since enzyme is a kind of protein, all factors that can affect protein will also affect enzyme, such as temperature and pH. Any enzyme has its most suitable temperature range. Within this range, the catalytic activity of the enzyme increases with increasing temperature, but if the temperature is higher or lower than the appropriate temperature range, the enzyme activity will decrease. When the temperature is too high (about greater than 60-70 ° C), the enzyme structure will be destroyed, so that the enzyme activity will be completely lost; on the contrary, if the temperature is too low, the enzyme will lose its activity, and this activity can be restored by the temperature rise. In addition, each enzyme also has its own suitable pH, for example, pepsin is suitable for acidic environment, trypsin is suitable for weak alkaline environment, but most enzymes work best in neutral solution.

Summary of enzymes:

The function of enzymes produced by the organism

1. Organisms synthesize proteins, some of which help metabolism, called enzymes.

1. Metabolism includes decomposition and synthesis of substances.

1. When enzymes help break down reactions, nutrients are broken down and energy is produced.

1. When enzymes help the synthesis reaction, different substances will be synthesized into new substances, providing growth and development.

Enzymes help metabolism

1. An enzyme can only help one metabolic reaction. For example, lipase only helps digest fat.

1. When the enzyme is decomposed, the enzyme first forms an enzyme-substance complex with the reactive substance before the substance can be decomposed into a decomposed substance.

1. When enzymes synthesize, enzymes first form enzyme-substance complexes with different reactive substances. Different reactive substances can be synthesized into new substances, called complexes.

1. Whether it helps the decomposition reaction or the synthesis reaction, the enzyme will not change the properties, and can continue to repeat the metabolism.

Enzymes are affected by temperature and pH

1. The ability of enzymes to assist in metabolic processes is called enzyme activity.

1. During metabolic reactions, changes in temperature and pH in the environment will affect enzyme activity.

1. Each enzyme can only be active in a certain range of suitable temperature and pH environment.

1. If the temperature is lower than appropriate, the enzyme will lose its activity, but the enzyme activity can be restored after increasing the temperature.

1. If the temperature is higher than appropriate, the enzyme will be destroyed and its activity will be completely lost. Moreover, it cannot be recovered after the temperature is lowered.

1. Generally, enzymes have the best activity when they are neutral, slightly acidic or alkaline; if they are too acidic or alkaline, the enzymes will lose their activity.