Thu 20 Jan, 2011 10:55 pm
the question is,, in a protein-specifying gene codes for combinations of 20 amino acids. but the human proteins contain 22 amino acids. how is this possible?
A clue is "essential v Nonessential" amino acids, eukaryotic proteinogenic amino acids. And evolution. ALL have something to do with it.
LAst hint: some essential amino acids are made by the breakdown of others.Proteinogenic amino acids are those amino acids that can be found in unique proteins and actually require unique cellular machinery in any organism for their production.