In nature, there are two groups of substances: organic and inorganic. The latter include compounds such as hydrocarbons, alkynes, alkenes, alcohols, lipids, nucleic and other acids, proteins, carbohydrates, amino acids. What are these substances for, we will tell in this article. The composition of all organic compounds certainly includes carbon atoms and hydrogen. They may also contain oxygen, sulfur, nitrogen and other elements. The science that studies proteins, acids, oxides, amino acids, - chemistry. She explores the properties and characteristics of each group of substances.
Amino acids - what are these substances for?
They are very important for the organism of any living creature on the planet, as they are a component of the most significant substances - proteins. In total, there are twenty-one amino acids from which these compounds are formed. The composition of each includes atoms of hydrogen, nitrogen, carbon and oxygen. The chemical structure of these substances has the amino group NH2, from which the name derives.
How are proteins made from amino acids?
These organic substances are formed in four stages, their structure consists of primary, secondary, tertiary and quaternary structures. Each of them depends on certain properties of the protein. Primary determines the number and order of amino acids located in the polypeptide chain. The secondary is an alpha helix or beta structure. The former are formed due to twisting of the polypeptide chain and the occurrence of hydrogen bonds within one.
The second - due to the occurrence of bonds between groups of atoms of different polypeptide chains. The tertiary structure is interconnected alpha helices and beta structures. It can be of two types: fibrillar and globular. The first is a long thread. Proteins with this structure are fibrin, myosin, located in muscle tissue, as well as others. The second has the appearance of a coil,
globular proteins include, for example, insulin, hemoglobin and many others. In the organism of living beings, special organelles of the cell â ribosomes â are responsible for the synthesis of proteins from amino acids. Information about the proteins that must be generated is encoded in DNA and transferred to the ribosomes using RNA.
What are the amino acids?
The compounds from which proteins are formed are twenty-one in nature. Some of them can be synthesized by the human body during metabolism (metabolism), while others are not. In general, such amino acids exist in nature: histidine, valine, lysine, isoleucine, leucine, threonine, methionine, phenylalanine, tryptophan, cysteine, tyrosine, arginine, alanine, glutamine, asparagine, glycine, proline, carnitine, ornithine, taurine, serine. The first nine of the above amino acids are indispensable. There are also conditionally irreplaceable ones - those that the body can use instead of the irreplaceable in extreme cases. This, for example, tyrosine and cysteine. The first can be used instead of phenylalanine, and the second - if there is no methionine. Essential amino acids in foods are a prerequisite for a healthy diet.
What foods do they contain?
- Valine - meat, fish.
- Histidine - buckwheat porridge, cereals, red fish, pork, poultry.
- Isoleucine - eggs, meat, fish, milk, cheese, cottage cheese.
- Leucine - the same as isoleucine.
- Methionine - cereals, peanuts, walnuts, pistachios, cereals.
- Threonine - meat, cereals, mushrooms.
- Tryptophan - turkey, rabbit, pork, horse mackerel.
- Phenylalanine - meat, beans, peas, lentils, soy, fish, cottage cheese, milk, cheese.
All other amino acids in the products consumed by humans may not be contained, since the body is able to produce them on its own, however, it is desirable that some of them come from food. Most essential amino acids are found in the same foods as essential ones, that is, meat, fish, milk - the kind of food that is rich in protein.
The role of each amino acid in the human body
Each of these substances performs a specific function in the body. The most essential amino acids for a full life are essential; therefore, it is very important to use foods with their sufficient amount.
Since protein is the main building material for our body, we can say that amino acids are the most important and necessary substances. Why the irreplaceable are needed, we will tell you now. As already mentioned above, this group of amino acids includes histidine, valine, leucine, isoleucine, threonine, methionine, phenylalanine, tryptophan. Each of these chemical compounds plays a specific role in the body. So, valine is necessary for full growth, therefore, products with its high content must necessarily be contained in sufficient quantities in the diet of children, adolescents and athletes who need to increase the concentration of muscle mass. Histidine also plays an important role - it participates in the process of tissue regeneration, is part of hemoglobin (which is why, with its low content in the blood, it is recommended to increase the amount of buckwheat cereal consumed). The body needs leucine in order to synthesize proteins, as well as to maintain the activity of the immune system at the proper level.
Lysine - without this substance, calcium will simply not be absorbed in the body, therefore it is impossible to prevent a shortage of this amino acid - you need to include more fish, cheese and other dairy products in your diet. Tryptophan is needed to produce vitamin B, as well as hormones that regulate hunger and mood. This substance is part of drugs that help calm and eliminate insomnia. Phenylalanine is used by the body to make hormones like tyrosine and adrenaline. This substance may also be part of medications prescribed for insomnia or depression.
Amino acids in terms of chemistry
You already know that the constituent proteins and vital substances for humans are amino acids. What are these compounds for, we have already considered, now we turn to their chemical properties.
Chemical properties of amino acids
Each of them is a little individual, although they have common features. Since the composition of amino acids can be different and include various chemical elements, the properties will be slightly different. A common feature for all substances of this group is the ability to condense to form peptides. Amino acids can also react with nitrous acid to form hydroxy acids, water and nitrogen.
In addition, they interact with alcohols. In this case, a hydrogen chloride salt of some ether and water are formed. Such a reaction requires the presence of
hydrochloric acid as a catalyst in a gaseous state of aggregation.
How to identify their presence?
To determine the presence of these substances, there are special qualitative reactions of amino acids. For example, to detect cysteine, you need to add lead acetate, and use heat and an alkaline environment. In this case, lead sulfide should form, which precipitates in black. Also, the amount of amino acid in a solution can be determined by adding nitrous acid to it. Recognize this by the amount of nitrogen released.