Amino acids are monomers that form the basis of vital proteins for the proper functioning of our body.
The amino acids are composed of an amino group (NH 2 ) that is a basic radical, and a carboxyl group (COOH) that is an acid group. The proteins of living beings are composed of the combination of 20 important amino acids for the body.
The binding of 2 amino acids is due to a peptide bond between the carbon of the carboxyl group of the first amino acid and the nitrogen of the amino group of the second amino acid. This binding releases a molecule of water and forms what is called a peptide.
The ligation of 2 or more peptides is called a polypeptide and, in turn, 1 or more polypeptide chains linked with a certain amino acid sequence and three-dimensional structure form a functional and mature protein. Depending on their structure, amino acids can be differentiated in the forms of L and D.
Amino acids structure
Amino acids are generally made up of a carbon, a carboxyl group (COOH), an amino group (NH 2 ), a hydrogen and a functional group called a side chain or group R.
In this sense, the carboxyl group is linked to the amino group through the same carbon (central atom), called alpha carbon. This carbon is associated with a hydrogen and an R group, which will determine the chemical behavior of the amino acid.
At the biological level, the 20 amino acids whose combinations form proteins have, therefore, different side chains. The simplest side chain is the one that constitutes the amino acid glycine, whose group R consists only of a hydrogen molecule.
The sequence and type of amino acids necessary to synthesize the proteins in the ribosomes are determined by the information contained in the messenger RNA (mRNA or mRNA).
In this sense, amino acids are essential elements for the creation of polypeptide chains (future proteins) that translate ribosomes through the work between mRNA and transfer RNA (tRNA).
Types of amino acids
There are a large number of amino acids, approximately, about 250 amino acids that are not part of the proteins and 20 amino acids that make up the proteins, also known as alpha-amino acids.
The 20 amino acids that make up the proteins are classified according to:
- the type of side chain or group R (hydrocarbons, neutrals, acid or base),
- its chemical behavior (acidic, basic, polar or non-polar), and
- whether it is synthesized or not by the human body (essential or non-essential).
However, beyond their classification all amino acids are important for the human body and to maintain a good state of health.
Essential amino acids
Essential amino acids are those that the human body is not able to generate and are obtained through food. Of the 20 amino acids, 10 are the essential ones: leucine, lysine, methionine, isoleucine, histidine, arginine, phenylalanine, threonine, valine and tryptophan.
Non-essential amino acids
The non-essential amino acids are 10 and are those that the body can synthesize. They are of great importance because they generate the proteins necessary for the proper functioning of the organism. The non-essential amino acids are: glycine, alanine, proline, serine, cysteine, glutamine, aspartic acid, glutamic acid, asparagine and tyrosine.
The 20 amino acids
The 20 amino acids whose combinations constitute the proteins necessary for the proper biochemical functioning of our organisms are called alpha-amino acids.
Below are the 20 alpha-amino acids along with their classification, according to the type of side chain or group R (hydrocarbons, neutral, acid or base), their chemical behavior (acidic, basic, polar or non-polar) and if it is synthesized or not by the human body (essential or non-essential).
Amino acid function
Amino acids fulfill various functions that are basic to the vital metabolic process of the organism, since they are the basis of proteins.
In this sense, amino acids share many of the functions of proteins, such as enzymatic and hormonal. Among its most important functions can be mentioned:
- Nutrient transport
- Repair or growth of body tissues.
- Storage of nutrients such as water, proteins, minerals, vitamins, carbohydrates and fats.
- They can provide energy.
- Maintains the balance of body acids.
- It allows muscle contraction.
- It allows the proper development and functioning of organs and glands.
- They are involved in the repair of tissues, skin and bones, as well as wound healing.
