Proteins!

Question 1

Each amino acid has a __________, ___________, ___________ and __________ around a central carbon.

Answer 1

Amino group, Hydrogen, carboxyl and R-group

Question 2

The four main function of proteins are:

Answer 2

1. Catalysis 2. Transport 3.. Structure

4. Motion

Question 3

The amino group on the amino acid carried the __________ charge.

Answer 3

Positive

Question 4

The ____________ group on the on the amino acid carried the negative charge.

Answer 4

Carboxyl group

Question 5

The ___________ gives each amino acid its unique properties

Answer 5

Side chain / R-group

Question 6

Name all the of the non-polar/ aliphatic amino acids in order of increasing hydrophobicity.

Answer 6

1. Glycine
2. Alanine
3. Valine
4. Leucine
5. Methionine
6. Isoleucine

Question 7

Name all the aromatic amino acids in order of increasing hydrophobicity.

Answer 7

1. Tyrosine
2. Tryptophan
3. Phenylalanine

Question 8

Name all the polar and uncharged amino acids.

Answer 8

Threonine, Serine, Cysteine, Proline, Asparagine, Glutamine

Question 9

Name all the polar and charged amino acids

Answer 9

Histidine, lysine and arginine

Question 10

Polar and negatively charged amino acids

Answer 10

Aspartate, Glutamate

Question 11

____________ has the ability to form disulfide bonds, which are important in protein stability and structure.

Answer 11

Cysteine

Question 12

Under oxidation conditions, disulphide bridges are _________ whereas under reduction conditions disulphide bridges are ___________

Answer 12

Formed; broken

Question 13

Human insulin is an example of how disulphide bridges can form _________ and ________ linkages.

Answer 13

Inter and intra chain linkages

Question 14

The post-translational ____________ is rich in collagen, yet without vitamin C, doesn’t occur and a person gets ___________

Answer 14

Hydroxyproline; Scurvy

Question 15

The post-translational ___________ is present in several different proteins involved in blood clotting. The lack of modification can be caused by _________ or ____________

Answer 15

Carboxyglutamate; vitamin K deficiency; Warfarin

Question 16

Post-translational glycosylation aids in _________, _________ and ___________

Answer 16

Stability, solubility and cell-signaling

Question 17

Gleevac is a tyrosine kinase inhibitor which inhibits reversible phosphorylation, leading to anti proliferation and treats ___________

Answer 17

Chronic Myelogenous Leukemia

Question 18

Ubiquitination adds a protein with ubiquitine ligase, which _______________

Answer 18

Sends the protein to the proteasome to be degraded.

Question 19

Proteasome inhibitor Valcade prevents Ubiquitination, which treats___________

Answer 19

Multiple Myeloma

Question 20

The peptide bond between the carbonyl carbon and the first amino acid the the amid nitrogen on the second amino acid has ______________ and cannot be rotated

Answer 20

Partial double-bond property

Question 21

The ________ angle is around the central carbon and amid nitrogen bond

Answer 21

Phi

Question 22

The _________ angle is around the central carbon and the carbonyl carbon bond.

Answer 22

Psi

Question 23

Not all Phi and Psi angles are possible because some rotations are inhibited by ____________

Answer 23

Steric crowding

Question 24

There are proteases that can digest any peptide bond such as _______, ________ or __________

Answer 24

Trypsin, Chymotrypsin and Pepsin

Question 25

Many blood clotting factors are proteases that exists in their ________ form until trauma initiated their _________

Answer 25

Inactive, Cleavage

Question 26

___________ between the protein backbone amide nitrogen and carbonyl oxygen are the driving force for the formation of protein secondary structures.

Answer 26

Hydrogen bonds

Question 27

______ and _____ connect alpha helix or beta sheets to form tertiary structures

Answer 27

Turns and Loops

Question 28

In an alpha helix, hydrogen bonds formed between the carbonyl oxygen of the _________ amino acid and the amide nitrogen of the __________ amino acid within the same polypeptide chain.

Answer 28

nth. n+4

Question 29

Some amin acids, _______ and _______ have a higher tendency to form form alpha helices.

Answer 29

Ala and Leu

Question 30

________ and ________ cannot form secondary structures such as alpha helices

Answer 30

Proline and Glycine

Question 31

Hemoglobin is mostly _________

Answer 31

alpha helical

Question 32

Fibrous tertiary structures are long, have one kind of secondary structure, ____________ and play a protective or structural role

Answer 32

insoluble

Question 33

What is a motif?

Answer 33

Arrangement of several secondary structure elements

Question 34

What is a domain?

Answer 34

Many proteins are made up of multiple stable globular units called domains with more or less independent functions.

Question 35

The most frequently found amino acids in turns and loops are _______ and __________

Answer 35

Glycine and proline

Question 36

What is Kd?

Answer 36

The binding strength is represented by the dissociation constant Kd

Question 37

Myglobin stores __________ for metabolism, and buries the ________ and oxygen inside the protein.

Answer 37

Oxygen; Heme

Question 38

Myglobin can store oxygen but cannot __________

Answer 38

Transport oxygen

Question 39

________ has a similar size and shape to O2, so it can fit into the same binding site

Answer 39

CO

Question 40

The relaxed state of hemoglobin is ___________

Answer 40

Holding onto Oxygen

Question 41

The tensed state of hemoglobin is _____________

Answer 41

Releasing Oxygen

Question 42

Positive cooperativity

Answer 42

The first bonding even increases the affinity of the remaining sites

Question 43

Oxygen binds well at a _________ pH such as in the lung

Answer 43

Higher

Question 44

Oxygen is releases well as a ___________ pH

Answer 44

Lower

Question 45

Crystallography

Answer 45

Analysis of X-ray diffraction pattern generated by protein crystals

Question 46

NMR

Answer 46

Analysis of magnetic resonance signal generate by high concentration of proteins within a magnetic field

Question 47

What does T (m) measure?

Answer 47

The temperature or chemical concentration where 50% of proteins are denatured.

Question 48

The Hsp70/Hsp40 folding chaperones are induced during ____________ and bind to the ___________ region of unfolded protein to prevent aggregation.

Answer 48

High temperatures; hydrophobic

Question 49

What does protein disulfide isomerase do?

Answer 49

Reduces improper disulfide bonds between free Cysteins and reforms them correctly

Question 50

What does propyl isomerase do?

Answer 50

Catalyzes the conversion between trans and cis proline which is required for the proper folding of some proteins

Question 51

Deletion of ________ in Cystic Fibrosis causes protein misfolding.

Answer 51

F508

Question 52

Gel filtration chromatography

Answer 52

Separates proteins based on their size differences

Question 53

Ion exchange chromatography

Answer 53

Separates proteins based on their charge differences

Question 54

Affinity Chromatography

Answer 54

Utilizes the ability of proteins to bind to specific ligands

Question 55

Edman degredation deteremines

Answer 55

N-terminus sequence of the protein

Question 56

Proteins can be identified on a __________ using protein specific __________

Answer 56

Western blot; Protein-specific antibodies

Question 57

A smaller Kd, means __________

Answer 57

Better binding affinity

Question 58

__________ is involved in N-glycosylation

Answer 58

Asparagine

Question 59

_____________ and ___________ are involved in turns and loops.

Answer 59

Proline and Glycine