What is the role of protease?
One of the main functions of proteases is to process proteins. Proteins in the body are difficult to digest and do not contain enzymes. Other types of proteases are involved in regulating the activities of blood clotting cells. These enzymes are also called proteolytic enzymes.
Proteins are held together by peptide bonds. Long-chain amino acids, small pieces of protein are called peptides, large pieces of protein are called peptides, and enzymes that break down peptides are called proteases. Proteases are types of proteins that accelerate degradation. γpeptidase cleaves terminal amino acids to break down peptide bonds and release amino acids produced due to residual protein.
What is protease?
Proteasomes are ubiquitous in eukaryotes and archaea, and a giant protein complex that also exists in some prokaryotes. In eukaryotes, the proteasome is located in the nucleus and cytoplasm. The main role of the proteasome is to degrade proteins that are not needed or damaged by the cell. This role is achieved by chemical reactions that break peptide bonds. Enzymes that can perform this role are called proteases.
The proteasome is the main mechanism used by cells to regulate specific proteins and remove misfolded proteins. After proteasome degradation, the protein is cleaved into peptides about 7-8 amino acids long; these peptides can be further degraded into single amino acid molecules, and then used to synthesize new proteins. The protein that needs to be degraded is first labeled (ie attached) by a small protein called ubiquitin. This labeling reaction is catalyzed by ubiquitin ligase. Once a protein is labeled with an ubiquitin molecule, it will trigger other ligases to add more ubiquitin molecules; this forms a “polyubiquitin chain” that can bind to the proteasome, thereby bringing the proteasome here. A labeled protein begins its degradation process.
From the structural point of view, the proteasome is a barrel-shaped complex, including a “core” composed of four stacked rings. The core is hollow to form a cavity. Among them, each ring is composed of seven protein molecules. The middle two loops each consist of seven β subunits and contain six active sites for proteases. These sites are located on the inner surface of the loop, so the protein must enter the “cavity” of the proteasome to be degraded.
The two outer rings each contain seven α subunits, which can function as a “gate” and are the only way for proteins to enter the “cavity”. These alpha subunits, or “gates”, are controlled by the “cap”-like structures (ie, regulatory particles) attached to them; the regulatory particles can recognize the polyubiquitin chain tag attached to the protein and initiate the degradation process. The entire system including ubiquitination and proteasome degradation is called the “ubiquitin-proteasome system”. The proteasome degradation pathway is essential for many cell processes, including the cell cycle, regulation of gene expression, and oxidative stress.
The winning themes of the Nobel Prize in Chemistry in 2004 were the importance of protein enzymolysis in cells and the role of ubiquitin in the enzymatic pathway. The three winners are Aaron Chehanovo, Avram Hershko and Owen Rose.
What is biological protease?
Biological protease is an abbreviation of enzyme that hydrolyzes protein peptide bond. This substance is generally widely distributed in plant stems and leaves, animal organs, microorganisms and fruits. The protease can accelerate the digestion of food after entering the human body, and has a relatively good help for indigestion that occurs in the human body. Protease also has a better recovery effect for some other types of diseases.
What is the role of pepsin?
Pepsin is a digestive protease whose main function is to break down the protein in food into small peptide fragments. Pepsin is mainly used to treat indigestion caused by eating too much protein food, or recovery period after serious illness, impaired digestion and chronic atrophic gastritis, as well as impaired digestive function of gastric cancer, and protease deficiency caused by pernicious anemia.