Group of the organic molecules composed of amino acids, basic amino acids (-NH2), acidic carboxyl groups (-COOH), and organic R groups (or side chains), is unique to each amino acid. The term amino acid α-amino [α-amino] is an abbreviation for carboxylic acid. Each molecule has a central carbon (C) atom called carbon, to which the amino and carboxyl groups are linked. The remaining two bonds of the β-carbon atom are usually satisfied by the hydrogen (H) atom and the R group.
What are amino acids?
Amino acids are carboxylic acids with amino groups. The most important type of amino acid is α-amino acid. Amino acids are mainly made up of carbon, nitrogen, oxygen, hydrogen, and other natural elements. We know about 500 amino acids, of which 20 are the most important and commonly used.
They are the second-largest component of the body when it builds muscles and tissues with water.
The general formula is given in the figure below.
Amino acid Structure
All 20 common amino acids include a carboxy group, an amino group, and a side chain (R group) that are all linked to α-carbon.
20 Types of Amino Acids
The following is a list of 20 common amino acids, as well as the three-letter and one-letter codes (uppercase) of amino acid symbols we often know. This paper is used for quick marking of amino acids and is easy to learn.
- alanine – ala – A
- arginine – arg – R
- asparagine – asn – N
- aspartic acid – asp – D
- cysteine – cys – C
- glutamine – gln
- glutamine – gln – Q
- glutamic acid – glu – E
- glycine – gly – G
- histidine – his – H
- isoleucine – ile – I
- leucine – leu – L
- lysine – lys – K
- methionine – met – M
- phenylalanine – phe – F
- proline – pro – P
- serine – ser – S
- threonine – thr – T
- tryptophan – trp – W
- tyrosine – tyr – Y
- valine – val – V
Classification of amino acids on the basis of R-group
- Non-polar, aliphatic amino acids: The R groups in these amino acids are non-polar and hydrophobic. Glycine, Elenin, Valine, Leucine, Isoleucine, Methionine, Proline.
- Aromatic amino acids: phenylalanine, tyrosine, and tryptophan and their aromatic side chains are relatively non-polar (hydrophobic). Anyone can participate in hydrophobic interactions.
- Polar, unchanged amino acids: Compared to non-polar amino acids, the R groups of these amino acids are more soluble in water, or more hydrophilic, as they contain functional groups that form hydrogen bonds with water. Such amino acids include serine, threonine, cysteine, asparagus, and glutamine.
- Acidic amino acids: R-groups are acidic or negatively charged amino acids. Glutamic acid and aspartic acid
- Basic amino acids: R-groups are basic or positively charged amino acids. Lysine, arginine, Histidine.
Classification of amino acids on the basis of nutrition
Amino Acids Essential
Nine types of amino acids cannot be synthesized in the body, so they must be present in the diet for protein synthesis.
These essential amino acids are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.
Amino Acids Non-essential
These amino acids can be synthesized in the body, so there is no need to get them through diet.
Arginine, glutamine, tyrosine, cysteine, glycine, proline, serine, ornithine, Elenin, asparagus, and aspartic acid.
Classification of Amino Acids