Amino acids, peptides, and protein II LO

Question 1

what are the 3 bonds that form the backbone of a polypeptide chain?

Answer 1

1. alpha carbon to carbonyl carbon within first amino acid
2. peptide bond between carbonyl carbon of 1st AA and amide nitrogen of 2nd
3. amid carbon of 2nd AA to alpha carbon of 2nd AA

Question 2

what determines the function of the protein?

Answer 2

the amino acid sequence brahhhhh

Question 3

what are 3 things that occur with amino acid sequence mutations?

Answer 3

1. misfolding or unstable proteins
2. truncated or extended proteins
3. proteins that no longer respond to regulation
   (all of these changes can cause disease)

Question 4

what is the function of a protease?

Answer 4

hydrolyze peptide bonds at specific amino acid sequences

Question 5

what does hydrolysis of peptide bonds do?

Answer 5

causes proteins to be active, causes proteins to degrade but mostly just activation of proteins

Question 6

what are the atoms that hydrogen bonds mostly form with?

Answer 6

H with N, O, F

Question 7

what is the location of hydrogen bonds in alpha helices?

Answer 7

carbonyl oxygen of nth AA with amid nitrogen of n+4th AA

Question 8

where do all of the side chains of an alpha helix face?

Answer 8

outward from the helix

Question 9

what is the relationship of the 1st 8 residues in an alpha helix?

Answer 9

stacked on top of each other

Question 10

how are beta sheets formed?

Answer 10

hydrogen bonds between 2 polypeptide chains

Question 11

what are the 2 orientations of beta sheets?

Answer 11

parallel and anti-parallel

Question 12

what is an example of a molecule made completely out of beta sheets?

Answer 12

immunoglobulin

Question 13

what kind of screw does an alpha helix form?

Answer 13

right handed screw

Question 14

how many residues are present per turn of the alpha helix?

Answer 14

3.6