Draw the structure for each of the following amino acids and put an asterisk (*) next to any chiral carbon centers in your structure:
b. lysine

Question

Draw the structure for each of the following amino acids and put an asterisk (*) next to any chiral carbon centers in your structure:

b. lysine

Accepted Answer

All right. Hello everyone. So this question is asking us which option shows the correct placement of an asterisk next to all chiral carbon atoms in the structure of amino acid cysteine. So here on the screen, after I scroll down, we can see the first three options labeled A through C and option D simply says that cystine has no chiral centers. So now let me scroll up. So you can see the structure of cysteine that I went ahead and drew on the screen here. So recalling first and foremost, the structure of cysteine, right? It's an amino acid which means that we have both an amino and a carboxylic acid group attaching to one alpha carbon at the center that alpha carbon is also connecting to the side chain, which in the case of cysteine contains a file group or sh group. So now what does it mean for a carbon atom to be chiral? Well, recall that chiral centers are ones specifically carbon atoms in which four different groups just write that down here, four different groups are attaching to that chiral carpet in order to make a chiral. So for example, right, the ch two found in the side chain of cysteine is not considered a chiral carbon because it has two of the same substituent, right. It has two hydrogens attached to it. Now, on the other hand, because of the structure inherent to an amino acid most of the time, except in the case of glycine, the alpha carbon is itself Cairo. So let's analyze that looking now at our alpha carbon here in the center of the structure. Let's see how many groups it's attached to. We have one hydrogen, one amino group, one carboxyl group and the side chain of cysteine itself. So here we have four different groups which means that the alpha carbon of cysteine is in fact chiral. So earlier, we established that the carbon atom of the side chain is not chiral and the carboxylic acid carbon is not chiral either. Therefore, cysteine only has one chiral center, which means that option A is correct here and there you have it. So with that being said, thank you so very much for watching. And I hope you found this helpful.

Draw the structure for each of the following amino acids and put an asterisk (*) next to any chiral carbon centers in your structure:
b. lysine

Verified video answer for a similar problem:

Key Concepts

Amino Acid Structure

Chirality

Lysine Structure

Draw the structure for each of the following amino acids and put an asterisk (*) next to any chiral carbon centers in your structure:b. lysine

Verified video answer for a similar problem:

Key Concepts

Amino Acid Structure

Chirality

Lysine Structure

Draw the structure for each of the following amino acids and put an asterisk (*) next to any chiral carbon centers in your structure:
b. lysine