Proteins

Question 1

Structural proteins

Answer 1

Collagen, elastin, keratin, actin, tubulin

Question 2

Motor proteins

Answer 2

Myosin, dynein, kinesin

Question 3

Binding protein

Answer 3

Hemoglobin

Question 4

Cell adhesion molecules

Answer 4

Cadherin, integrin, selectin

Question 5

In gel electrophoresis, the cathode is

Answer 5

Negatively charged, attracts cations (+)

Question 6

In gel electrophoresis, the anode is

Answer 6

Positively charged, attracts anions (-)

Question 7

In gel electrophoresis, which charged molecules have greater velocity

Answer 7

Highly charged molecules

Question 8

Native PAGE limitations

Answer 8

Different proteins with similar size-to-charge ratios might have same migration velocity

Question 9

SDS-PAGE

Answer 9

Eliminates charge by neutralization wth SDS, only compares size of proteins

Question 10

Migration velocity equation

Answer 10

v = Ez/f (E = electric field, z = net charge, f = friction dependent on size)

Question 11

Isoelectric focusing

Answer 11

Proteins are separated based on their isoelectric point (pI)

Question 12

In isoelectric focusing, positively charged proteins migrate to the

Answer 12

Cathode (basic gel, OH-)

Question 13

In isoelectric focusing, negatively charged proteins migrate to the

Answer 13

Anode (Acidic gel, H+)

Question 14

Ion exchange chromatography

Answer 14

Beads in column are coated with charged substances e.g. positively charged column will attract negatively charged molecules and increase retention time

Question 15

Column chromatography

Answer 15

Polar molecules travel slower, molecules similar to the mobile phase (solvent) travel faster

Question 16

Size-exclusion chromatography

Answer 16

Smaller molecules get caught in beads and travel slower, larger molecules travel faster

Question 17

Affinity chromatography

Answer 17

Create column with high affinity for the protein e.g. antibody, receptor

Question 18

Protein structure techniques

Answer 18

X-ray crystallography and NMR spectroscopy

Question 19

Protein activity techniques

Answer 19

Bradford assay, UV spectroscaphy

Question 20

X-ray crystallography measures

Answer 20

Electron density, can be used for nucleic acids

Question 21

Amino acid composition technique

Answer 21

Hydrolysis -> chromatography

Question 22

Edman degradation

Answer 22

Cleave N-terminus of proteins

Question 23

Hydrolysis limitation

Answer 23

Doesn’t give amino acid sequence

Question 24

Bradford assay

Answer 24

Dye binds to proteins, gives up H+, turns blue

Question 25

UV spectroscopy

Answer 25

No treatment

Question 26

SDS-PAGE limitation

Answer 26

Protein cannot be recovered from gel