AP BIOLOGY

BIOCHEMISTRY

ENZYMES AND METABOLISM

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Select the properties that R groups of amino acids can possess that they affect how the protein folds into its three dimensional shape (multiple answers possible).
A
Some are polar (hydrophilic).
B
Some are non-polar (hydrophobic).
C
Some are positively or negatively charged.
D
Some contain sulfur.
Explanation: 

Detailed explanation-1: -The R groups have a variety of shapes, sizes, charges, and reactivities. This allows amino acids to be grouped according to the chemical properties of their side chains. For example, some amino acids have polar side chains that are soluble in water; examples include serine, threonine, and asparagine.

Detailed explanation-2: -Primarily, the interactions among R groups creates the complex three-dimensional tertiary structure of a protein. The nature of the R groups found in the amino acids involved can counteract the formation of the hydrogen bonds described for standard secondary structures such as the alpha helix.

Detailed explanation-3: -When protein folding takes place (in an aqueous compartment), the hydrophobic R groups of nonpolar amino acids will cluster together in the interior of the protein, whereas the hydrophilic R groups lay on the outside. These types of interactions are known as hydrophobic interactions.

Detailed explanation-4: -The R group determines the characteristics (size, polarity, and pH) for each type of amino acid.

There is 1 question to complete.