Proteins - w2

Question 1

What’s an example of a transport protein?

Answer 1

hemoglobin

Question 2

What’s an example of a storage protein?

Answer 2

ferritin

Question 3

Which proteins are functional and water-soluble?

Answer 3

globular proteins

Question 4

Which proteins are structural, linear polymers with repeating units?

Answer 4

fibrous proteins

Question 5

Which proteins are a subunit of globular proteins and can cross lipid membranes?

Answer 5

transmembrane proteins

Question 6

Which proteins are a subunit of globular proteins and has domains for histones?

Answer 6

DNA-binding proteins

Question 7

What are the four levels of protein structure?

Answer 7

primary (single polypeptide chain), secondary (helix or sheet), tertiary (folds)m quaternary (1+ tertiary proteins)

Question 8

What kind of reaction occurs in the binding of amino acids to make a polypeptide chain?

Answer 8

condensation reaction

Question 9

What does the N-terminal consist of?

Answer 9

the amino group

Question 10

What does the C-terminal consist of?

Answer 10

carboxyl group

Question 11

What’s another name for the terminals?

Answer 11

residues

Question 12

What stabilizes a-helices?

Answer 12

hydrogen bonds between NH and CO groups (4 AAs apart)

Question 13

What is the helix breaker and cannot form into a-helix because the NH is already bonded?

Answer 13

proline

Question 14

How does a parallel beta sheet bond?

Answer 14

one AA residue to two AA residues on the other strand

Question 15

How does an anti-parallel beta sheet bond?

Answer 15

one AA residue to one AA residue

Question 16

What do we call beta turns that connect strands of antiparallel b-sheets?

Answer 16

beta loop (hairpin bend) held together by a stable hydrogen bond

Question 17

What do we call the physically independent regions on a tertiary structure?

Answer 17

structural domains

Question 18

What bond in a tertiary confirmation is between positively and negatively charged AAs?

Answer 18

ionic bonds

Question 19

What bond in a tertiary confirmation can occur between two cysteine residues?

Answer 19

disulfide bond

Question 20

Which domain of a transmembrane tertiary protein is the binding site for hormones?

Answer 20

ligand-binding domain (Extracellular)

Question 21

Where do we find the G-protein binding domain in a transmembrane protein?

Answer 21

intracellular domain

Question 22

Which post-translational modifications occur intracellularly?

Answer 22

phosphorylation

Question 23

Where do glycosidic bonds occur?

Answer 23

extracellularly

Question 24

What are the structure of soluble globular proteins?

Answer 24

charged aa’s are on surface in contact with water, non-polar (hydrophobic) aa’s in the cor

Question 25

Three tertiary structured proteins are called what?

Answer 25

trimers

Question 26

What do we consider each peptide chain in a quaternary structure?

Answer 26

functional subunit (not domains)

Question 27

What is the native conformation pattern?

Answer 27

non-random and regulated (determined by genetic code)

Question 28

What is protein denaturation?

Answer 28

unfolding and disruption of secondary and tertiary structures (DOESNT DESTROY BONDS)

Question 29

What are the five common protein denaturing agents?

Answer 29

heat, ph changes, urea, organic solvents, detergents

Question 30

What does ER stress / protein misfolding cause in our cells?

Answer 30

proteotoxic stress

Question 31

What is Alzheimer’s disease caused by?

Answer 31

accumulation of misfolded amyloid proteins in the brain (plaques)

Question 32

What prion disease causes neurodegeneration, due to misfolding?

Answer 32

CJD and mad cow disease