Q. 16.61 - An Introduction to General, Organic, and Biological Chemistry

Question

a. Draw the condensed structural formula for Ser-Lys-Asp. 

b. Would you expect to find this segment at the center or at the surface of a protein? Why?

Step-by-Step Solution

Answer

(Part a)

a)

                           

(Part b) 

b)

     Polar R-group amino acids make up this peptide.

     As a result, they can be found on the surface of the protein structure.

step-1 Given information (part-a)

• Amino acids have two functional groups: An amine  $\left(-{\mathrm{NH}}_2\right)$and a carboxylic acid $(-\mathrm{COOH})$. The a-carbon is covalently linked to both functional groups.
•  All proteins are constructed from aminoacids. 
• A dipeptide is generated when two aminoacids are joined by an amide bond formed between the amine group of one amino acid and the carboxylic group of the second aminoacid.
•  Proteins are macromolecules made up of aminoacids, which are repeating subunits that dictate the form and function of the protein.

step-2 Explanation (part-a)

 

step-3 Given information (part-b)

• The aliphatic side chains of hydrophobic aminoacids make them water insoluble. 
• These hydrophobic amino acids are present inside the protein structure, 
• whereas hydrophilic amino acids have polar side chains and can be found on the surface or outside.

step-4 Explanation (part-b)

 

• This peptide comprises polar R-group amino acids.
•  As a result, they are present on the protein structure's surface.