Q. 16.12 - An Introduction to General, Organic, and Biological Chemistry

Question

16.12 Draw the condensed structural formula for cach of the following peptides, and give its three-letler and one-letler abbreviations:

a. prolyl aspartate

b. threonyl leucine

c. methionylglutaminyllysine

d. histidylglycylghutamylisoleucine

Step-by-Step Solution

Answer

The structures of peptides are shown below, along with the one-letter and three-letter amino acid abbreviations:

(Part a)

(Part b) 

(Part c)

(Part d) 

Step 1: Introduction(Part a)

Amino acids are the building blocks of proteins. These contain one hydrogen atom, one amine group $\left(-{\mathrm{NH}}_2\right)$, one carboxylic acid group $(-\mathrm{COOH})$  and one side chain (R group) attached to the central carbon atom.

The hydroxyl group of the carboxylic acid and the hydrogen group of the amino group combine to form a water molecule and an amide linkage. The "peptide bond" is an amide bond formed between one amino acid's carboxylic group and the amino group of another amino acid.

Step 2: Given data (Part a)

Peptide structures are shown below, along with one-letter and three-letter amino acid prolyl aspartate abbreviations.

Step 3: Explanation (part a)

Step 4: Given data (Part b)

Peptide structures are shown below, along with one-letter and three-letter amino acid threonyl leucine  abbreviations.

Step 5: Explanation (part b)

Step 6: Given data (Part c)

Peptide structures are shown below, along with one-letter and three-letter amino acid methionylglutaminyllysine  abbreviations:

Step 7: Explanation (part c)

Step 8: Given data (Part d)

Peptide structures are shown below, along with one-letter and three-letter amino acid histidylglycylghutamylisoleucine  abbreviations.

Step 9: Explanation (part d).