Proteins (class info)

Question 1

What bond is peptide bond analogous with?

Answer 1

Phosphodiester bond

Question 2

how do you know the type of bond?

Answer 2

By electronegativity. The more right and up- increases

Question 3

Why do hydrogen bonds form between the carboxyl group and amino group?

Answer 3

Due to the electronegativity difference between Carbon and nitrogen a polar covalent bond forms. That results in a partially negative charge for the Oxygen from the Carbon group and a partially positive charge in the nitrogen group. Thus, it results in an attraction between the positive and negative charge.

Question 4

What is the difference between alpha helix and beta pleated? ( not structural)

Answer 4

Alpha helix has a hydrogen bond between teh Oxygen and the 4th amino acid’s carbon. It is a horizontal bond.
Beta pleated has a hydrogen bond between the carbonyl and amino vertically

Question 5

Describe the structural capabilities of a beta pleated structure and the functions that correlate with it.

Answer 5

It is tough, rigid and fibrous –>structural functions

Question 6

What are the 4 types fo R-group interactions?

Answer 6

1. Hydrogen bonds- (b/w polar a.a.)
2. Ionic bonds- charged R groups
3. Hydrophobic Interactions
4. Disulfide bonds(s-s)- between cysteine subunits

Question 7

Describe nonpolar amino acid structures

Answer 7

C-H; carbon ring structure, Nitrogen

Question 8

Describe polar amino acid structures

Answer 8

partial charge; oxygen; sulfur

Question 9

Describe ionic amino acids

Answer 9

acidic- negative charge
basic- positive charge
negative charged acidic ionic bonds w/ basic positive charge

Question 10

Describe disulfide bridge

Answer 10

cysteine- cysteine bond; interior
–> strong covalent bonds; reinforce structure

Question 11

Describe hydrophobic interactions

Answer 11

Weak interactions
In aqueous solutions, hydrophobic a.a. gets pushed to the interior- water forces them to bond

Question 12

What is the amino acid switch in sickle cell anemia?

Answer 12

Glutamic acid which is polar is switched with valine which is non polar- messes up the chain

Question 13

Define the primary structure

Answer 13

consists of amino acids linked by peptide bonds defines the ultimate structure and function of the protein.

Question 14

Define the secondary structure

Answer 14

The secondary protein structure forms between hydrogen bonds from the amino and carbonyl group from the primary structure which are bonded together by peptide bonds. Results in either two structures: alpha helix or beta pleated