please explain the polypeptide chain given in ncert with serine, alanine, glutamic acid, tyrosin and cystiene
Polypeptide chain- Polypeptides are polymers of alpha amino acids. Amino acids are organic acids containing an amino group (-NH2) and an carboxylic acid group ( -COOH), as substituent, attached on the same carbon. This carbon is called alpha carbon. There are 4 substituent groups that occupy the four valency positions of this carbon, namely an amino group, an acidic group, a hydrogen and a variable group R group. R group is third substituent on this carbon.
. Different R groups are present on different amino acids, or we can say that,. due to the presence of these different R groups amino acids are different from each other. The fourth substituent of this alpha carbon is a hydrogen group.
In glycine R group is hydrogen ( -H)
Alanine - R group is methyl group ( - CH3)
Serine - R group is hydroxyl methyl group ( -CH2OH)
Glutamic acid- This is an acidic amino acids, since acidic R group is present.
Tyrosine- This is aromatic amino acids. The side chain contain one aromatic ring
Cysteine- Cysteine is amino acids with sulphur containing R group ( - CH2HS)
The figure and the amino acid chain represents the primary structure of protein i.e it gives the position of first, second and so on amino acids in the protein.
The N (-NH2 side) and C (-COOH side) represent two terminals of the protein. It shows suppose, in the protein chain there are "n" number of amino acids, the position of serine is taken as n-2, cysteine is n-1, tyrosine is n, and glutamic acid is n+1 and so on.
. Different R groups are present on different amino acids, or we can say that,. due to the presence of these different R groups amino acids are different from each other. The fourth substituent of this alpha carbon is a hydrogen group.
In glycine R group is hydrogen ( -H)
Alanine - R group is methyl group ( - CH3)
Serine - R group is hydroxyl methyl group ( -CH2OH)
Glutamic acid- This is an acidic amino acids, since acidic R group is present.
Tyrosine- This is aromatic amino acids. The side chain contain one aromatic ring
Cysteine- Cysteine is amino acids with sulphur containing R group ( - CH2HS)
The figure and the amino acid chain represents the primary structure of protein i.e it gives the position of first, second and so on amino acids in the protein.
The N (-NH2 side) and C (-COOH side) represent two terminals of the protein. It shows suppose, in the protein chain there are "n" number of amino acids, the position of serine is taken as n-2, cysteine is n-1, tyrosine is n, and glutamic acid is n+1 and so on.