Question 1

Hydrophobic interaction chromatography can be used to separate proteins based on differences in

Accepted Answer

A)  ionic charge.
B)  solubility.
C)  size.
D)  polarity.
E)  binding specificity.F) A) and B)
G) C) and D)

Question 2

Matching
-In ______ chromatography, a protein mixture must be applied to the column at a low pH so that the proteins will have a net positive charge and bind to the column.

Accepted Answer

A)  electrophoresis
B)  hydrophobic interaction
C)  enzyme-linked immunosorbent assay
D)  three-dimensional shape
E)  N-terminal amino acidF) negative chargeG) nucleasesH) chromophoreI) foamingJ) high level expressionK) 2-mercaptoethanolL) positive chargeM) cation exchangeN) pIO) chymotrypsinP) C-terminal amino acidQ) Sodium dodecyl sulfateR) F) and Q)
S) E) and N)

Question 3

Proteins are often constructed from multiple segments of 40-200 amino acid residues, commonly called

Accepted Answer

A)  pseudogenes.
B)  hypervariable residues.
C)  protolytic fragments.
D)  domains.
E)  subunits.F) A) and C)
G) B) and D)

Question 4

A protein that has had few changes in its amino acid sequence over evolutionary history is labeled

Accepted Answer

A)  a fibrinopeptide.
B)  evolutionarily conserved.
C)  random.
D)  a product of pseudogenes.
E)  phylogenetic.F) B) and C)
G) A) and B)

Question 5

The salting in of proteins can be explained by:

Accepted Answer

A)  salt counter-ions reducing electrostatic attractions between protein molecules.
B)  salt ions reducing the polarity of the solution.
C)  salt ions increasing the hydrophobic interactions.
D)  releasing hydrophobic proteins from nonpolar tissue environments.
E)  hydration of the salt ions reducing solubility of proteins.F) C) and D)
G) A) and C)

Question 6

Matching
-In general, proteins are least soluble in water when the pH is close to the ______.

Accepted Answer

A)  electrophoresis
B)  hydrophobic interaction
C)  enzyme-linked immunosorbent assay
D)  three-dimensional shape
E)  N-terminal amino acidF) negative chargeG) nucleasesH) chromophoreI) foamingJ) high level expressionK) 2-mercaptoethanolL) positive chargeM) cation exchangeN) pIO) chymotrypsinP) C-terminal amino acidQ) Sodium dodecyl sulfateR) G) and Q)
S) C) and L)

Question 7

A technique that can be used to separate proteins based primarily on their pI is called

Accepted Answer

A)  ion-exchange chromatography.
B)  gel filtration chromatography.
C)  affinity chromatography.
D)  isoelectric focusing.
E)  hydrophobic interaction chromatography.F) B) and C)
G) A) and E)

Question 8

You are purifying a nuclease by affinity chromatography.To determine which fractions contain the protein of interest, you test samples of all fractions for their ability to break down DNA.This is an example of

Accepted Answer

A)  a binding assay.
B)  a biological assay.
C)  an enzyme assay.
D)  an immunological assay.
E)  none of the aboveF) D) and E)
G) C) and D)

Question 9

Which of these reagents is commonly used to determine the number of polypeptides in a protein?

Accepted Answer

A)  iodoacetate
B)  dansyl chloride
C)  2-mercaptoethanol ( β\betaβ -M
E)  
D)  cyanogen bromide
E)  DEAE F) None of the above
G) C) and D)

Question 10

What can be done to increase the rate at which a protein of interest moves down an ion-exchange chromatography column?

Accepted Answer

A)  reduce the ion concentration in the eluant
B)  add a small amount of a non-ionic detergents to the eluant
C)  change the pH of the eluant
D)  add a protease inhibitor to the eluant
E)  reduce the temperature of the eluantF) A) and E)
G) A) and B)

Question 11

A variety of chromatographic techniques are available for protein purification.
a.Explain briefly the principle of hydrophobic interaction chromatography.
b.Name three changes that can be made to the eluant that can be used to speed up elution of the protein of interest from a hydrophobic interaction chromatography column.

Accepted Answer

a.The column material is substituted wit...

Question 12

Matching
-If the cDNA for a protein has been cloned, it may be possible to obtain large quantities of the protein by _________________ in bacteria.

Accepted Answer

A)  electrophoresis
B)  hydrophobic interaction
C)  enzyme-linked immunosorbent assay
D)  three-dimensional shape
E)  N-terminal amino acidF) negative chargeG) nucleasesH) chromophoreI) foamingJ) high level expressionK) 2-mercaptoethanolL) positive chargeM) cation exchangeN) pIO) chymotrypsinP) C-terminal amino acidQ) Sodium dodecyl sulfateR) I) and O)
S) B) and J)

Question 13

You have purified the receptor for a hormone by affinity chromatography.During gel filtration chromatography under native conditions the receptor elutes between pyruvate decarboxylase (250 kDa)and glutamine synthetase (620 kDa).During SDS-PAGE, in the absence of reducing agents, the receptor migrates as a single band of approximately 230 kDa.When SDS-PAGE is carried out in the presence of 2-mercaptoethanol the receptor migrates as two bands of approximately 95 and 135 kDa.Explain this result.

Accepted Answer

The receptor is a heterotetramer compose...

Question 14

A radioimmunoassay requires

Accepted Answer

A)  an enzyme-linked antibody.
B)  a coupled enzymatic reaction.
C)  a radiolabeled antibody.
D)  a catalytic antibody.
E)  a radiolabeled standard protein that is used to compete for binding to the antibody.F) B) and D)
G) B) and E)

Question 15

Disulfide bonds can be cleaved using

Accepted Answer

A)  iodoacetate.
B)  dansyl chloride.
C)  2-mercaptoethanol ( β\betaβ -M
E)  .
D)  trypsin.
E)  phenylisothiocyanate. F) B) and E)
G) A) and B)

Question 16

Matching
-Molecules that contain a(n) ______ are capable of absorbing light.

Accepted Answer

A)  electrophoresis
B)  hydrophobic interaction
C)  enzyme-linked immunosorbent assay
D)  three-dimensional shape
E)  N-terminal amino acidF) negative chargeG) nucleasesH) chromophoreI) foamingJ) high level expressionK) 2-mercaptoethanolL) positive chargeM) cation exchangeN) pIO) chymotrypsinP) C-terminal amino acidQ) Sodium dodecyl sulfateR) A) and O)
S) K) and P)

Question 17

We are able to purify proteins because they differ from each other in various physical or chemical properties.List 5 physicochemical properties of proteins that can be used as basis for their separation.Give a method of separation based on each of these properties (match the method with the property).

Accepted Answer

1.solubility - salting out; 2.ionic char...

Question 18

An enzyme-linked immunosorbent assay requires

Accepted Answer

A)  a radioactive substrate.
B)  a radioactive standard for binding to the antibody.
C)  aromatic amino acids.
D)  an antibody that binds the protein of interest.
E)  a catalytic antibody.F) B) and E)
G) A) and B)

Question 19

A technique that can be used to separate proteins based primarily on the presence of non-polar residues on their surface is called

Accepted Answer

A)  ion-exchange chromatography.
B)  gel filtration chromatography.
C)  affinity chromatography.
D)  gel electrophoresis.
E)  hydrophobic interaction chromatography.F) D) and E)
G) C) and D)

Question 20

ELISA is an example of a(n) :

Accepted Answer

A)  enzyme assay.
B)  biological assay.
C)  binding assay.
D)  immunological assay.
E)  none of the aboveF) A) and B)
G) A) and C)

Exam 5: Proteins: Primary Structure

Correct Answer
verified
a.The column material is substituted wit...
View Answer

Matching -In ______ chromatography, a protein mixture must be applied to the column at a low pH so that the proteins will have a net positive charge and bind to the column.

Correct Answer
verified

Correct Answer
verified
1.solubility - salting out; 2.ionic char...
View Answer

Correct Answer
verified
The receptor is a heterotetramer compose...
View Answer

Which of these reagents is commonly used to determine the number of polypeptides in a protein?

Correct Answer
verified

ELISA is an example of a(n) :

Correct Answer
verified

You are purifying a nuclease by affinity chromatography.To determine which fractions contain the protein of interest, you test samples of all fractions for their ability to break down DNA.This is an example of

Correct Answer
verified

A technique that can be used to separate proteins based primarily on the presence of non-polar residues on their surface is called

Correct Answer
verified

Matching -If the cDNA for a protein has been cloned, it may be possible to obtain large quantities of the protein by _________________ in bacteria.

Correct Answer
verified

An enzyme-linked immunosorbent assay requires

Correct Answer
verified

A radioimmunoassay requires

Correct Answer
verified

The salting in of proteins can be explained by:

Correct Answer
verified

Matching -In general, proteins are least soluble in water when the pH is close to the ______.

Correct Answer
verified

A technique that can be used to separate proteins based primarily on their pI is called

Correct Answer
verified

Proteins are often constructed from multiple segments of 40-200 amino acid residues, commonly called

Correct Answer
verified

Hydrophobic interaction chromatography can be used to separate proteins based on differences in

Correct Answer
verified

Disulfide bonds can be cleaved using

Correct Answer
verified

What can be done to increase the rate at which a protein of interest moves down an ion-exchange chromatography column?

Correct Answer
verified

A protein that has had few changes in its amino acid sequence over evolutionary history is labeled

Correct Answer
verified

Matching -Molecules that contain a(n) ______ are capable of absorbing light.

Correct Answer
verified

Exam 5: Proteins: Primary Structure

Correct Answerverifieda.The column material is substituted wit...View AnswerShow Answer

Matching -In ______ chromatography, a protein mixture must be applied to the column at a low pH so that the proteins will have a net positive charge and bind to the column.

Correct AnswerverifiedShow Answer

Correct Answerverified1.solubility - salting out; 2.ionic char...View AnswerShow Answer

Correct AnswerverifiedThe receptor is a heterotetramer compose...View AnswerShow Answer

Which of these reagents is commonly used to determine the number of polypeptides in a protein?

Correct AnswerverifiedShow Answer

ELISA is an example of a(n) :

Correct AnswerverifiedShow Answer

You are purifying a nuclease by affinity chromatography.To determine which fractions contain the protein of interest, you test samples of all fractions for their ability to break down DNA.This is an example of

Correct AnswerverifiedShow Answer

A technique that can be used to separate proteins based primarily on the presence of non-polar residues on their surface is called

Correct AnswerverifiedShow Answer

Matching -If the cDNA for a protein has been cloned, it may be possible to obtain large quantities of the protein by _________________ in bacteria.

Correct AnswerverifiedShow Answer

An enzyme-linked immunosorbent assay requires

Correct AnswerverifiedShow Answer

A radioimmunoassay requires

Correct AnswerverifiedShow Answer

The salting in of proteins can be explained by:

Correct AnswerverifiedShow Answer

Matching -In general, proteins are least soluble in water when the pH is close to the ______.

Correct AnswerverifiedShow Answer

A technique that can be used to separate proteins based primarily on their pI is called

Correct AnswerverifiedShow Answer

Proteins are often constructed from multiple segments of 40-200 amino acid residues, commonly called

Correct AnswerverifiedShow Answer

Hydrophobic interaction chromatography can be used to separate proteins based on differences in

Correct AnswerverifiedShow Answer

Disulfide bonds can be cleaved using

Correct AnswerverifiedShow Answer

What can be done to increase the rate at which a protein of interest moves down an ion-exchange chromatography column?

Correct AnswerverifiedShow Answer

A protein that has had few changes in its amino acid sequence over evolutionary history is labeled

Correct AnswerverifiedShow Answer

Matching -Molecules that contain a(n) ______ are capable of absorbing light.

Correct AnswerverifiedShow Answer

Correct Answer
verified
a.The column material is substituted wit...
View Answer

Correct Answer
verified

Correct Answer
verified
1.solubility - salting out; 2.ionic char...
View Answer

Correct Answer
verified
The receptor is a heterotetramer compose...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

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