JEE PYQ: Biomolecules And Polymers Question 20
Question 20 - 2020 (03 Sep Shift 2)
The number of $>\text{C}=\text{O}$ groups present in a tripeptide Asp-Glu-Lys is ____.
Show Answer
Answer: 5
Solution
Asp-Glu-Lys tripeptide: $\text{H}_2\text{N}-\text{CH}-\overset{\text{O}}{\text{C}}-\text{NH}-\text{CH}-\overset{\text{O}}{\text{C}}-\text{NH}-\text{CH}_2-\text{COOH}$ with side chains $\text{CH}_2\text{COOH}$, $\text{CH}_2\text{CH}_2\text{COOH}$, and $(\text{CH}_2)_4\text{NH}_2$. No. of C=O groups = 5 (2 peptide bonds + 3 from COOH groups).
BETA
