BCHS 3304_Exam 2 (CH 5 - CH 7) || with Error-free Answers.
Discuss the disadvantages of each in handling proteins:
(a) low concentration of proteins
(b) sudsing of protein solutions
(c) lack of sterile conditions
(d) Absence of protease inhibitors
(e) warm environments
(f) pH's far from neutrality correct answers (a) This makes it difficult to recover a lot of proteins
because a lot of them are denatured when the come into contact with certain surfaces.
(b) this means a lot of contact with air or water can cause proteins to be denatured.
(c) Fungi or bacteria can infect the protein and end up eating or destroying it.
(d) If enzymes like protease are made inactive can denature the protein.
(e) Most proteins cannot survive above 25 degrees Celsius.
(f) the pH determines the protein's structure which determines whether the protein can properly
react or not.
When are proteins the least soluble? correct answers Proteins are the least soluble at their
isoelectric point (pI).
What other factors determines a protein's solubility? correct answers 1. The polar groups a
protein has the more soluble it is.
2. The more ionized the protein is the more soluble it is.
3. The shorter the peptide the more soluble it is.
-Ex: You have 2 Leucines. One has 3 residues and the other has 10 residues. The one with 3
residues is more soluble.
Explain ELISA correct answers This is an enzyme-linked immunosorbent assay.
, What is salting in? correct answers When there is low ion concentration, protein solubility
increases when salts are added.
(a)What is salting out? (b)What is salting out used for? How does it work? correct answers (a)
When too much salt is added, the protein solubility decreases.
(b) Salting out is used for separating proteins based on their solubility. Proteins precipitate at
different salt concentrations.
What is Ion Exchange Chromatography? correct answers This is when anion or cation exchange
occurs.
-low affinity: move faster through column
-high affinity: move slower through column
What is Absorption Chromatography? correct answers Proteins are separated based on solubility
(a) What is Gel Filtration Chromatography?
(b) What is NOT a factor in this method? correct answers (a) This is separates molecules based
on size and shape.
(b)
(a) What is Affinity Chromatography?
(b) What happens to proteins that cannot bind? correct answers (a) This type of chromatography
uses a matrix-bound ligand to collect certain types of proteins. (b)The proteins that do not bind
the matrix-bound ligand exit along with buffer.
What is chromatograpy? correct answers This is a method used to separate molecules based on a
specific property.
(a) What is SDS-PAGE? What does SDS-PAGE separate by?
Discuss the disadvantages of each in handling proteins:
(a) low concentration of proteins
(b) sudsing of protein solutions
(c) lack of sterile conditions
(d) Absence of protease inhibitors
(e) warm environments
(f) pH's far from neutrality correct answers (a) This makes it difficult to recover a lot of proteins
because a lot of them are denatured when the come into contact with certain surfaces.
(b) this means a lot of contact with air or water can cause proteins to be denatured.
(c) Fungi or bacteria can infect the protein and end up eating or destroying it.
(d) If enzymes like protease are made inactive can denature the protein.
(e) Most proteins cannot survive above 25 degrees Celsius.
(f) the pH determines the protein's structure which determines whether the protein can properly
react or not.
When are proteins the least soluble? correct answers Proteins are the least soluble at their
isoelectric point (pI).
What other factors determines a protein's solubility? correct answers 1. The polar groups a
protein has the more soluble it is.
2. The more ionized the protein is the more soluble it is.
3. The shorter the peptide the more soluble it is.
-Ex: You have 2 Leucines. One has 3 residues and the other has 10 residues. The one with 3
residues is more soluble.
Explain ELISA correct answers This is an enzyme-linked immunosorbent assay.
, What is salting in? correct answers When there is low ion concentration, protein solubility
increases when salts are added.
(a)What is salting out? (b)What is salting out used for? How does it work? correct answers (a)
When too much salt is added, the protein solubility decreases.
(b) Salting out is used for separating proteins based on their solubility. Proteins precipitate at
different salt concentrations.
What is Ion Exchange Chromatography? correct answers This is when anion or cation exchange
occurs.
-low affinity: move faster through column
-high affinity: move slower through column
What is Absorption Chromatography? correct answers Proteins are separated based on solubility
(a) What is Gel Filtration Chromatography?
(b) What is NOT a factor in this method? correct answers (a) This is separates molecules based
on size and shape.
(b)
(a) What is Affinity Chromatography?
(b) What happens to proteins that cannot bind? correct answers (a) This type of chromatography
uses a matrix-bound ligand to collect certain types of proteins. (b)The proteins that do not bind
the matrix-bound ligand exit along with buffer.
What is chromatograpy? correct answers This is a method used to separate molecules based on a
specific property.
(a) What is SDS-PAGE? What does SDS-PAGE separate by?
