00:04
So in order to answer the questions as to whether any of the amino acids, the structure shown in table 22, 20 .2, i would look at that table and go through them one by one.
00:21
And so what we're looking for here, of course, the alpha carbon that the carboxylate and the amino group, the alpha hydrogen, and the r group are all bonded to.
00:34
That carbon is always going to be chiral except in glycine where there are two hydrogens bonded to it.
00:43
So glycine doesn't even have one.
00:46
Now for all of the others, that alpha carbon is one, and it's a question of whether there is another one on the amino acid side chain.
00:57
And so let's take them one by one.
00:59
Remember that if any carbon atom has two atoms or groups bonded to it, such as two hydrogens or two metals that are the same, then that carbon is not chiral.
01:12
And so in alanine, the side chain carbon has three hydrogens.
01:17
It's not chiral.
01:18
In valine, that first carbon has a hydrogen bonded, and it's bonded to the main, the rest of the amino acid.
01:28
But it's bonded to two metals.
01:32
And so that carbon that's bonded to the two metals, and of course the methyl carbons also are not chiral.
01:39
In leucine, the first carbon coming from the alpha, that is the beta carbon is a ch2.
01:48
And so it is not chiral.
01:50
And then the next carbon has a ch, but again, two methyl groups bonded to it.
01:56
So no other chirals...