Proteins are complex protein molecules arranged in a solid structure. Their formation in cells is called protein biosynthesis. Proteins can consist of several 1,000 amino acids. They are indispensable building blocks of all living organisms.
What is protein biosynthesis?
Proteins are complex protein molecules arranged in a solid structure. Their formation in cells is called protein biosynthesis. Proteins are synthesized from amino acids in a complex biochemical process. This takes place at the ribosomes of a cell. Although a protein has a complex structure, the ribosome receives the exact information in which order the amino acids must be linked together. The information about the structure of the protein is stored in the DNA. A human gene consists of 23 chromosomes in duplicate, with the exception of the male Y chromosome. Each chromosome thus has two or one long DNA strand. It is wound up in a fixed shape (double helix) with the help of proteins in a complex process. Humans have about 25,000 genes, so that about 1,000 genes are stored on one chromosome. As a rule, one gene is responsible for the synthesis of a protein. In order for a protein to be synthesized, the DNA of the protein must be transported from the cell nucleus to the ribosomes. For this purpose, the body makes a copy of the gene, the messenger RNA or mRNA. This copy migrates into the cell plasma to the ribosomes, where it is encoded. The ribosomes attach themselves to the chromosome strand and make the new protein molecules. This process is called translation. Now the protein chain unfolds into its final form and detaches from the ribosomes.
Function and task
During protein biosynthesis, the complete genetic code of an amino acid chain is translated and converted into a three-dimensional structure. This process is controlled by the genetic code of the nucleus. Protein biosynthesis is vital because proteins influence almost all processes in the human body. They are also responsible for our appearance. The protein structure is genetically determined. Ribosomes do not work like machines and sometimes even follow random reaction pathways. Although chance plays a role in individual reaction steps, ribosomes nevertheless work extremely reliably and almost never incorporate the wrong amino acids into the chain. As elementary building blocks of the organism, proteins are found in all tissue structures as well as body fluids. The permanent supply of proteins is necessary for the maintenance of the body substance, in which degradation and remodeling processes permanently take place, for healing, reproduction and growth as well as for the production of structures. Strength athletes hope to use dietary proteins to stimulate protein synthesis in muscle and build more muscle. The availability of amino acids can stimulate protein synthesis, but opinions differ on the extent to which this occurs. However, it has been proven that even the healthy body with decreasing muscle mass is less able to cope with stressful situations. To build up a permanent supply of amino acids for performance enhancement reasons is nevertheless controversial, because if the concentration of amino acids in the blood is very high over a long period of time, the body simply switches off protein biosynthesis. Thus, to achieve an increase in muscle mass, time is more significant than the amount of protein. Growth factors such as insulin affect protein biosynthesis because they can stimulate the uptake of amino acids. These performance-enhancing drugs are prohibited as doping in competitive sports.
Diseases and ailments
The complex process of protein biosynthesis is prone to disruption. Aging and disease are the biggest influencers of protein biosynthesis. The correct position and orderly advancement of transfer RNA (translocation) are particularly important for the smooth progression of synthesis. If this is impaired, health is at risk, because microorganisms now have an easy game. Many diseases are associated with the interference of protein biosynthesis, for example through the activity of enzymes. One focus of medical research relates to structural insights into the function and binding sites of antibiotics. The latest antibiotics act directly on protein biosynthesis at ribosomes.The antibiotic interferes with synthesis by docking directly onto ribosomes to kill unwanted pathogens on the spot. Amino acids stimulate the formation of mitochondria, the power plants of cells. Cells that consume a lot of energy, for example skeletal and cardiac muscles, have particularly large numbers of mitochondria. Activity generates energy and stimulates metabolic processes. In degenerative muscle diseases, muscle movement is particularly important to activate protein biosynthesis. If protein production declines, the goal is often increased amino acid mobilization. Hormones can also control muscle function. Testosterone, for example, is known for its anabolic effect because it stimulates protein production and promotes muscle growth. Protein folding disorders prevent the correct folding of the protein filament and have serious consequences. The cause is thought to be a gene mutation. Misfolded proteins produce different diseases, and the cells always respond with stress. Because the transaction is suppressed, the synthesis of harmful substances is increased. Also, already vitamin deficiency can lead to disorders of protein biosynthesis. Among the vitamins, vitamin B6 has the strongest influence on protein synthesis. A deficiency causes nerve damage, skin changes, growth disorders and muscle atrophy. Acquired disorders of protein biosynthesis are mainly liver inflammation and liver cirrhosis. Inflammation leads to changes in amino acid sequence. Errors in transcription or translation and severe infectious diseases can also produce misfolding. Today, biochemists are trying to calculate the dynamics of protein biosynthesis in order to cure genetically caused diseases. These findings, in turn, have implications for all cellular processes.
