Q.16.22 - An Introduction to General, Organic, and Biological Chemistry

Question

What type of interaction would you expect between the R groups of the following amino acids in a quaternary structure?

a. phenylalanine and isoleucine

b. glutamate and arginine

c. asparagine and tyrosine

d. alanine and proline

Step-by-Step Solution

Answer

a. hydrophobic interaction

b. ionic interaction 

c. hydrogen bonding interaction 

d. hydrophobic interaction 

Part (a) Step 1: Given Information

phenylalanine and isoleucine

Determining the type of interaction between the R groups of phenylalanine and isoleucine in a quaternary structure

Part (a) Step 2: Explanation

Phenylalanine is a fragrant fundamental amino acid, non-polar and it is hydrophobic because of the latent benzyl side chain. Isoleucine is an aliphatic fundamental, nonpartisan, nonpolar amino acid and it is likewise hydrophobic because of the latent methyl side chain. 

The interaction of R bunches among phenylalanine and isoleucine is hydrophobic interaction.

Part (b) Step 1: Given Information

glutamate and arginine

Determining the type of interaction between the R groups of glutamate and arginine in a quaternary structure

Part (b) Step 2: Explanation

Glutamate is an adversely charged, polar, superfluous amino acid containing a carboxylic acid group. Arginine is a decidedly charged, polar semi fundamental or restrictively amino acid containing amino group. Also, arginine is amphiphile (both hydrophilic and lipophilic). In light of response conditions, it shows a positive charge guanidium bunch profoundly polar toward the finish of the hydrophobic aliphatic hydrocarbon chain. 

Hence it is an ionic interaction.

Part (c) Step 1: Given Information

asparagine and tyrosine

Determining the type of interaction between the R groups of asparagine and tyrosine in a quaternary structure

Part (c) Step 2: Explanation

Asparagine and tyrosine both are impartial, polar amino acids. Asparagine contains the carboxylic acid group. Tyrosine contains polar hydroxyl bunch it can take part in hydrogen bond development with either carboxylic acid gathering or an amide gathering of asparagine to make hydrogen bond interaction. Hence it is an hydrogen bonding interaction.

Part (d) Step 1: Given Information

alanine and proline
Determining the type of interaction between the R groups of alanine and proline in a quaternary structure

Part (d ) Step 2: Explanation

Alanine and Proline both amino acids are trivial and non-polar. Both amino acids contain amide bunch and carboxylic acid gathering. Hence it is hydrophobic interaction.