1|Page
BIOC 384 EXAM 2|| QUESTIONS AND 100%
CORRECT ANSWERS ALREADY GRADED A+||
LATEST AND COMPLETE UPDATE WITH
VERIFIED SOLUTIONS GUARANTEED PASS!!!
What is the purpose of a biochemical assay in protein purification?
To uniquely identify a protein of interest.
What enzyme is mentioned as being used in a biochemical assay?
Luciferase, found in bioluminescent organisms.
What reaction does luciferase catalyze with ATP?
It oxidizes D-luciferin to produce oxyluciferin and light.
What happens to luciferase when exposed to heat?
It becomes denatured.
What is cell fractionation?
A process that provides proteins from freshly isolated cells, bio fluids, and tissues.
What is the purpose of disrupting cells during cell fractionation?
,2|Page
To create a cell extract (homogenate) without inactivating proteins.
What method uses ultrasonic waves to disrupt cell membranes?
Sonication.
How does shearing disrupt cells?
By forcing cells through a small opening using a tight-fitting Teflon plunger.
What is the purpose of centrifugation in protein purification?
To separate cellular components into fractions called pellet and supernatant.
What are the four fractions obtained from centrifugation?
Nuclei, mitochondria, plasma membrane components, and cytosol.
What is specific activity in the context of protein purification?
The total amount or activity of the target protein divided by the total amount of
protein in the fraction.
What does A280 measurement indicate?
The absorbance due to aromatic residues in proteins.
, 3|Page
What is the process of salting out in protein purification?
Adding saturated salt to a protein solution to precipitate proteins.
What is dialysis used for in protein purification?
To leave protein in a buffer of proper ionic strength and pH.
What is the principle behind column chromatography?
It is a protein purification method using a solid matrix and an aqueous buffer.
What is gel filtration chromatography also known as?
Size-exclusion chromatography.
How do small proteins behave in gel filtration chromatography?
They elute last because they are caught by porous matrix beads.
What is ion exchange chromatography based on?
The net charge of proteins based on the pH of the buffer used.
BIOC 384 EXAM 2|| QUESTIONS AND 100%
CORRECT ANSWERS ALREADY GRADED A+||
LATEST AND COMPLETE UPDATE WITH
VERIFIED SOLUTIONS GUARANTEED PASS!!!
What is the purpose of a biochemical assay in protein purification?
To uniquely identify a protein of interest.
What enzyme is mentioned as being used in a biochemical assay?
Luciferase, found in bioluminescent organisms.
What reaction does luciferase catalyze with ATP?
It oxidizes D-luciferin to produce oxyluciferin and light.
What happens to luciferase when exposed to heat?
It becomes denatured.
What is cell fractionation?
A process that provides proteins from freshly isolated cells, bio fluids, and tissues.
What is the purpose of disrupting cells during cell fractionation?
,2|Page
To create a cell extract (homogenate) without inactivating proteins.
What method uses ultrasonic waves to disrupt cell membranes?
Sonication.
How does shearing disrupt cells?
By forcing cells through a small opening using a tight-fitting Teflon plunger.
What is the purpose of centrifugation in protein purification?
To separate cellular components into fractions called pellet and supernatant.
What are the four fractions obtained from centrifugation?
Nuclei, mitochondria, plasma membrane components, and cytosol.
What is specific activity in the context of protein purification?
The total amount or activity of the target protein divided by the total amount of
protein in the fraction.
What does A280 measurement indicate?
The absorbance due to aromatic residues in proteins.
, 3|Page
What is the process of salting out in protein purification?
Adding saturated salt to a protein solution to precipitate proteins.
What is dialysis used for in protein purification?
To leave protein in a buffer of proper ionic strength and pH.
What is the principle behind column chromatography?
It is a protein purification method using a solid matrix and an aqueous buffer.
What is gel filtration chromatography also known as?
Size-exclusion chromatography.
How do small proteins behave in gel filtration chromatography?
They elute last because they are caught by porous matrix beads.
What is ion exchange chromatography based on?
The net charge of proteins based on the pH of the buffer used.
