DNA is transcribed to form mRNA in the nucleus. The mRNA is then exported to the cytoplasm. mRNA is then translated into a linear sequence of amino acids that folds into a 3D structure.
Amino acids have an alpha carbon central to it. Surrounding the alpha carbon is the amino group, carboxylic acid, and amino acid specific side chain (R group).
When the R group is not a hydrogen atom, the alpha carbon is an asymmetric center.
At a neutral pH, the amino acid nitrogen is protonated and the carboxylic acid is deprotonated to yield a zwitterion.
When four different groups are attached to a carbon atom, the atom is said to be chiral, a stereocenter, or an asymmetric carbon.
A Fischer projection is a 2D stereochemical representation.
All 20 alpha amino acids, except glycine, contain an asymmetric alpha carbon.
L-alanine is the mirror image of D-alanine, so they are enantiomers.
The classifications of amino acids are nonpolar aliphatic, nonpolar, nonpolararomatic, polar, positively charged polar, and negativitychargedpolar amino acids.
The nonpolar aliphatic amino acids are glycine, alanine, valine, leucine, and isoleucine.
The nonpolar amino acids are proline and methionine.
The nonpolar amino acids are phenylalanine, tyrosine, and tryptophan.
The polar amino acids are serine, cysteine, threonine, asparagine, and glutamine.
The positively charged polar amino acids are histidine, lysine, and arginine.
The negatively charged polar amino acids are asparticacid and glutamicacid.
Glycine (Gly, G)
Alanine (Ala, A)
Valine (Val, V)
Leucine (Leu, L)
Isoleucine (Ile, I)
Proline (Pro, P)
Methionine (Met, M)
Phenylalanine (Phe, F)
Tyrosine (Tyr, Y)
Tryptophan (Trp, W)
Serine (Ser, S)
Cysteine (Cys, C)
Threonine (Thr, T)
Asparagine (Asn, N)
Glutamine (Gln, Q)
Histidine (His, H)
Lysine (Lys, K)
Arginine (Arg, R)
Asparticacid (Asp, D)
Glutamic acid (Glu, E)
The one letter abbreviation for alanine is A.
The three letter abbreviation for alanine is Ala.
The one letter abbreviation for arginine is R.
The three letter abbreviation for arginine is Arg.