Amino acids are fundamental molecules in the biological processes that occur in living beings. Its importance lies in its role in the formation of proteins, key substances for the functioning of organisms. In this article, we are going to explore what amino acids are, their characteristics and their relevance in human biochemistry and physiology.
What are amino acids?
Amino acids are organic compounds that contain an amino group (-NH2) and a carboxyl group (-COOH) attached to a central carbon known as the alpha carbon (a). Additionally, this alpha carbon is attached to a hydrogen group and a side chain that varies in each type of amino acid. The basic structure of an amino acid is represented as follows:
There are 20 common amino acids found in proteins of living organisms, and are classified into essential and non-essential amino acids. Essential amino acids are those that the human body cannot synthesize on its own, so it is necessary to obtain them through food. On the other hand, non-essential amino acids can be synthesized by the body from other molecules.
Characteristics of amino acids
1. Chemical properties
Amino acids are amphoteric compounds, that is, they can behave as both acids and bases depending on the pH of the medium in which they are found. This is due to the presence of acidic and basic groups in its molecular structure. Amino groups can accept protons, acting as bases, while carboxyl groups can give up protons, behaving like acids.
2. Functional groups
In addition to the amino and carboxyl groups, amino acids contain an R group, also known as a side chain, which gives unique characteristics to each type of amino acid. The variability in the R groups is what determines the individual properties of each amino acid, such as its polarity, solubility and chemical reactivity.
3. Enantiomeric structure
Amino acids have an asymmetric central carbon, which gives them the property of being chiral molecules, that is, they exist in enantiomeric forms or stereoisomers. This means that amino acids have a mirror shape that is not superimposable with their mirror image. In nature, amino acids usually occur in their L form, although there are exceptions.
4. Peptide bondAmino acids are joined together by peptide bonds to form proteins. The peptide bond is formed through a condensation reaction in which a water molecule is released. This union is established between the amino group of one amino acid and the carboxyl group of another, generating a linear chain of amino acid residues.5. Biological functions
Amino acids perform various biological functions in living organisms. In addition to being the basic components of proteins, they also act as neurotransmitters, precursors of bioactive molecules and as sources of energy. Some amino acids have specific functions, such as the synthesis of hormones and enzymes, or as structural elements of tissues and cells.
Importance of amino acids
Amino acids are essential to maintain life and the proper functioning of the body. Their participation in the structure of proteins gives them a fundamental role in cellular processes such as protein synthesis, nutrient transport, immune response and tissue repair. A lack of amino acids in the diet can lead to health problems and nutritional deficiencies.
In summary, amino acids are key molecules in the biology and chemistry of living beings. Their versatile structure and functions give them an essential role in the regulation of numerous physiological and biochemical processes. Understanding the nature and characteristics of amino acids is essential to advance our knowledge of life and its fundamental mechanisms.