Peptides and Proteins

Question 1

What is Ehlers-Danlos Syndrome?

Answer 1

Defect in structure, production, or process of collagen or proteins interacting with collagen

Question 2

Polypeptide chains are what?

Hint: shape

Answer 2

Planar

Question 3

What are amino acids joined covalently by in a peptide chain?

Answer 3

Amide bonds

Question 4

What are proteins also known as?

Answer 4

Polypeptides

Question 5

Proteins have a _____ backbone of _____ different side chains protruding.

Answer 5

Repeating; 20

Question 6

What is the order of chemical interactions that stabilizes a polypeptide?

Answer 6

Covalent bond > Disulfide bond > Salt bridge > Hydrogen bond > Van der waals

Question 7

What happens during a secondary structure?

Answer 7

Polypeptides begin to fold

Question 8

In a secondary structure, hydrogen bonding occurs every ____ amino acids.

Answer 8

4

Question 9

What is the primary stabilizing feature for polypeptides in a secondary structure?

Answer 9

Hydrogen bonds

Question 10

An alpha helix is a what kind of turn?

Answer 10

Right hand

Question 11

Beta strand makes up what?

Answer 11

Beta sheets

Question 12

A beta strand has alternating ____?

Answer 12

R groups

Question 13

In an antiparallel BETA sheet, the adjacent B tuns in what direction?

Answer 13

Opposite

Question 14

What groups connect each amino acid to a single amino acid on adjacent strands?

Answer 14

NH and CO groups

Question 15

In a parallel BETA sheet, the adjacent b runs in what direction?

Answer 15

Same

Question 16

In a BETA sheet, the side chains are located where?

Answer 16

Above and below the plane

Question 17

In a tertiary structure, hydrophobic amino acids are found where?

Answer 17

On the inside

Question 18

What are found on the protein surface of a tertiary structure?

Answer 18

Charged amino acids (hydrophilic amino acids)

Question 19

Primary structures have what kind of backbone?

Answer 19

Linear

Question 20

Secondary structures can consist of what?

Answer 20

Alpha helix, Beta sheets, reverse turns

Question 21

What is involved inside a tertiary structure?

Hint: DHH

Answer 21

Disulfide bonds, hydrogen bonding, hydrophobic interactions

Question 22

In protein denaturation, OIL is what?

Answer 22

Oxidation losing e-

Question 23

In protein denaturation, RIG is what?

Answer 23

Reduction is gaining e-

Question 24

What is B-mercaptoethanol?

Answer 24

1. reducing agent that gains H

2. breaks disulfide bonds

Question 25

8m urea is what kind of substance?

Answer 25

Harsh substance to denature

Question 26

A native ribonuclease is what kind of structure?

Answer 26

Tertiary structure

Question 27

A denatured reduced ribonuclease is what kind of structure?

Answer 27

Primary structure

Question 28

In amino acid detection, Trp + Tyrosine = _____ when subjected to UV spec?

Answer 28

280nm

Question 29

What is used for sequencing a peptide?

Answer 29

Edman degradation allows sequencing of a peptide

Question 30

To study a primary structure, what can be used?

Answer 30

Mass spectroscopy, Proteases, Edman degradation

Question 31

When studying a secondary structure, what can be used?

Answer 31

Circular dichroism (CD) spectroscopy

Question 32

What does a CD spectroscopy do?

Answer 32

Depolarizes light substances depending on secondary structure

Question 33

What can be used when studying a tertiary structure?

Answer 33

X-ray crystallography

Question 34

What is the strongest type of chemical reaction that stabilizes a protein?

Answer 34

Covalent bond

Question 35

What is the weakest type of chemical interaction that stabilizes a peptide?

Answer 35

Van der Waals interaction

Question 36

What two things denature a ribonuclease?

Answer 36

8 M Urea and B-mercaptoethanol

Question 37

Which procedure reveals the entire sequence of a peptide?

Answer 37

Edman degradation

Question 38

With Edman degradation, what can be released without hydrolyzing the rest of the peptide?

Answer 38

Amino-terminal residue

Question 39

Trypsin cleaves at the carboxyl end of what amino acids?

Answer 39

Arginine and lysine

Question 40

Chymotrypsin cleaves at the carboxyl end of what amino acids? Hint: PTT

Answer 40

Phenylalanine, tyrosine, tryptophan

Question 41

CNBR cleaves at the end of what amino acid?

Answer 41

Methionine

Question 42

Denaturation can cause the loss of what structures due to unfolding of the polypeptide chain?

Answer 42

Secondary, tertiary, and quaternary