About amino acids
High-Yield facts on Amino Acids
All amino acids found in proteins exist in L-form
Amino acids have 2 isomers i,e D and L forms. As each amino acid has one chiral carbon.
Remember the exceptions : Glycine does not have any chiral carbon, so no optical activity and no isomers.
Isoleucine and Threonine have 2 chiral carbons each, so four optical isomers each.
Maximum absorption of light is shown by Tryptophan.
Note that only aromatic AA absorb light.
Largest amino acid- Tryptophan
Smallest amino acid- Glycine
Most acidic amino acid- Aspartate
Most basic amino acid – Arginine
Most polar amino acid – Glutamine
Most non-polar amino acid – Phenylalanine
Amino acid with Imino group – Proline
Amino acid with Indole group – Tryptophan
Amino acid with Guanidium group – Arginine
21st amino acid is Selenocysteine.
It is coded by codon UGA (usually it is a stop codon).
22nd amino acid is Pyrolysine
It is coded by UAG