Question

Which of the following statements correctly completes the statement?
Except for glycine, which is achiral, all the amino acids present in proteins

• A. are chiral but racemic
• B. have the $L$ configuration at their $\alpha$ carbon
• C. have the $R$ configuration at their $\alpha$ carbon
• D. have the $S$ configuration at their $\alpha$ carbon

Answer 1

The correct option is B have the $L$ configuration at their $\alpha$ carbon

Glycerine is the only amino acid which is achiral because it has 2 Hydrogen atoms attached to the alpha carbon.

All the amino acids present in proteins have the L configuration at their $\alpha$ carbon.This is because D- Amino Acids are not naturally found in proteins.

So Option b is correct