Module 6

Question 1

aim to produce a relatively large quantity of purified proteins for subsequent use.

Answer 1

Preparative purifications

Question 2

produces a relatively small amount of a protein for variety of research or analytical purposes, including identification, structural characterization, and studies of protein’s structure, post-translational
modification, and function.

Answer 2

Analytical purification

Question 3

• Is a series of processes intended to isolate and purify a single protein or complex from cells, tissues, or whole organisms.
• Is vital for characterization of the function, structure, and interactions of the protein of interest.

Answer 3

Protein Purification

Question 4

• to develop reagents like enzymes and antibodies that can be used as molecular biology tools for
  understanding cellular processes.

Answer 4

Biological research

Question 5

• purified proteins are used to develop assays and tests for diseases.

Answer 5

Diagnostics

Question 6

• protein-based biosensors are used to detect
  contaminants.

Answer 6

Environmental monitoring

Question 7

• protein content in food and cosmetic products must
  fulfill certain safety standards due to the risk of allergic reactions

Answer 7

Food and cosmetics

Question 8

• utilizes proteins for identifying substances in criminal investigations.

Answer 8

Forensic science

Question 9

• purified proteins are pivotal for drug development and production, including therapeutic proteins and
  vaccines.

Answer 9

Biopharmaceutical development

Question 10

The source of a protein is generally _______ or _______

Answer 10

tissue or microbial cells.

Question 11

process of rupturing the plasma membrane (includes bacterial/plant cell wall) to release the protein from the cell

Answer 11

Homogenization

Question 12

• Utilizes ultrasonic waves to disrupt cell membranes
• Quick approach commonly used for bacterial cells and is very effective for small volumes

Answer 12

Sonication

Question 13

• Solubilize cell membranes by disrupting lipid bilayers.
• This process is easy to use and very effective for membrane proteins, but it can cause denaturation if used at high concentrations.

Answer 13

Detergents

Question 14

• Solvents such as ethanol or acetone are used to precipitate proteins and disrupt membranes.
• It is a quick approach, but it is not suitable for all protein types, as it can cause denaturation.

Answer 14

Organic solvents

Question 15

• Disrupt the hydrogen bonding network in proteins, aiding in solubilization.
• Examples include urea and guanidine hydrochloride.
• This approach is especially useful for insoluble proteins but can denature proteins and often requires subsequent refolding steps.

Answer 15

Chaotropic agents

Question 16

• Involves repeated cycles of freezing and thawing to lyse cells by ice crystal formation.
• It is a simple way to lyse cells since it doesn’t require special equipment.
• However, it is time-consuming and not very efficient for some cell types.

Answer 16

Freeze-thawing

Question 17

• Sometimes enzymes, such as lysozymes, are used to break down bacterial cell walls, in combination with other methods for enhanced efficiency.
• This approach is very specific and maintains protein integrity.
• Its use is limited to bacterial cells and requires additional steps for a complete cell lysis.

Answer 17

Enzymatic treatment

Question 18

solubility of proteins is generally lowered at high salt concentrations, an effect called

Answer 18

salting out

Question 19

often used to salt out proteins.

Answer 19

Ammonium sulfate

Question 20

a procedure that separates proteins from small
solutes by taking advantage of the proteins’ larger size.

Answer 20

Dialysis

Question 21

What does IEC stand for?

Answer 21

Ion Exchange Chromatography

Question 22

What does SEC stand for?

Answer 22

Size Exclusion Chromatography

Question 23

What does HIC stand for?

Answer 23

Hydrophobic Interaction Chromatography

Question 24

separates components based on their density by spinning samples at high speeds.

Answer 24

Centrifugation

Question 25

used to prepare subcellular fractions or to isolate specific organelles

Answer 25

Differential centrifugation

Question 26

extract is subjected to treatments that separate the proteins into different fractions based on a property such as size or charge, a process referred to as

Answer 26

fractionation