Introduction to Simplest amino acid:
Amino acids are simple organic molecules containing both amino (-NH2 group) and carboxylic acid group (-COOH). In actual practice, the term amino acid is used with reference to α – amino carboxylic acids which are isolated from natural sources. The discovery of amino acid was started in the year 1806 with the isolation of “Asparagine” from “Asparagus juice”, which is obtained from natural sources. In the year 1820, the first amino acid was isolated from protein material. A high molecular weight protein like gelatin was cleaved by digestion with dilute acid (Hydrolysis). The cleavage product was separated and a major product was identified as simplest amino acid termed glycine as common name. Many other amino acids have been isolated from non-protein sources such as antibiotics, bacterial cell wall, biochemical metabolites in plants and animals. More than 100 amino acids have isolated and identified but only 20 amino acids are of general occurrence because they are found in all proteins. All the natural amino acids that occur as a constituent of proteins and are optically active compounds except simplest amino acid (glycine) are optically inactive. Although some of the amino acids in proteins are dextro rotator and some of them are Levo - rotatory at PH =7. Amino acids are colorless and crystalline solids which are used in the formation of amino acid peptide. Amino acids are generally insoluble in non – polar solvents like ether, benzene etc., but soluble in polar solvents like water. However, some amino acids are almost insoluble in water. Amino acids can react with both acids and bases. Amino acid has Zwitter ion structure. In solution, the Zwitter ion is in equilibrium with the covalent form of the amino acid. The Zwitter ion is an amino acid molecule containing both positive and negative charge. Amino acid exhibit Iso electric point. It is the PH of the solution at which amino acid does not move either to the cathode or to the anode.
Formation of peptide bond by simplest amino acid:
When two simplest amino acid molecules combine, a reaction takes place between the carboxyl group of one amino acid and the amino group of the other with the elimination of water molecule. The resultant bond formed between the two amino acid molecules is called peptide bond (or also called amino acid peptide bond). An amino acid peptide bond is an amide bond (-CONH-) formed between the two amino acid molecules.
H2N-CH2-COOH + HNH-CH2-COOH → H2N-CH2-CONH-CH2-COOH + H2O
Glycine Glycine Dipeptide
Thus amino acid peptide is a linear polymer chemistry consisting of large number of amino acids with molecular weight less than 10,000 and protein molecule as molecular weight more than 10,000.
Peptide bonds:
The joining of amino acids in the process of making biochemical molecules like proteins is done by bonds which are referred to as peptide bonds. This may be illustrated with the two simplest amino acids, glycine and alanine.
Properties of Simplest amino acid (Glycine):
Simplest amino acid (Glycine) is a neutral amino acid.
Simplest amino acid (Glycine) belong to Non – Essential amino acid. Non – Essential amino acids are the one which are synthesized by the human body.
Amino acids are simple organic molecules containing both amino (-NH2 group) and carboxylic acid group (-COOH). In actual practice, the term amino acid is used with reference to α – amino carboxylic acids which are isolated from natural sources. The discovery of amino acid was started in the year 1806 with the isolation of “Asparagine” from “Asparagus juice”, which is obtained from natural sources. In the year 1820, the first amino acid was isolated from protein material. A high molecular weight protein like gelatin was cleaved by digestion with dilute acid (Hydrolysis). The cleavage product was separated and a major product was identified as simplest amino acid termed glycine as common name. Many other amino acids have been isolated from non-protein sources such as antibiotics, bacterial cell wall, biochemical metabolites in plants and animals. More than 100 amino acids have isolated and identified but only 20 amino acids are of general occurrence because they are found in all proteins. All the natural amino acids that occur as a constituent of proteins and are optically active compounds except simplest amino acid (glycine) are optically inactive. Although some of the amino acids in proteins are dextro rotator and some of them are Levo - rotatory at PH =7. Amino acids are colorless and crystalline solids which are used in the formation of amino acid peptide. Amino acids are generally insoluble in non – polar solvents like ether, benzene etc., but soluble in polar solvents like water. However, some amino acids are almost insoluble in water. Amino acids can react with both acids and bases. Amino acid has Zwitter ion structure. In solution, the Zwitter ion is in equilibrium with the covalent form of the amino acid. The Zwitter ion is an amino acid molecule containing both positive and negative charge. Amino acid exhibit Iso electric point. It is the PH of the solution at which amino acid does not move either to the cathode or to the anode.
Formation of peptide bond by simplest amino acid:
When two simplest amino acid molecules combine, a reaction takes place between the carboxyl group of one amino acid and the amino group of the other with the elimination of water molecule. The resultant bond formed between the two amino acid molecules is called peptide bond (or also called amino acid peptide bond). An amino acid peptide bond is an amide bond (-CONH-) formed between the two amino acid molecules.
H2N-CH2-COOH + HNH-CH2-COOH → H2N-CH2-CONH-CH2-COOH + H2O
Glycine Glycine Dipeptide
Thus amino acid peptide is a linear polymer chemistry consisting of large number of amino acids with molecular weight less than 10,000 and protein molecule as molecular weight more than 10,000.
Peptide bonds:
The joining of amino acids in the process of making biochemical molecules like proteins is done by bonds which are referred to as peptide bonds. This may be illustrated with the two simplest amino acids, glycine and alanine.
Properties of Simplest amino acid (Glycine):
Simplest amino acid (Glycine) is a neutral amino acid.
Simplest amino acid (Glycine) belong to Non – Essential amino acid. Non – Essential amino acids are the one which are synthesized by the human body.
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