Pharmaceutical Biotechnology Questions and Answers for Campus interviews on “Methods of Immobilization”.
1. Why are Enzymes active only over small range of pH?
a) Its enzymes property
b) Due to non-active site functional group charges
c) Due to the active site functional group charges
d) It prevents from structure destruction
Answer: c
Clarification: Enzyme are active only over small range of pH due to the active site functional group charges (ionic form) and the three dimensional shape of enzyme are pH-dependent. Certain enzyme have ionic group on their active sites, and these ionic group must be in a suitable form (acid or base) to function.
2. What is the suitable form of ionic group of enzymes?
a) Acidic or basic
b) Acidic
c) Basic
d) neutral
Answer: a
Clarification: Certain enzyme have ionic group on their active sites, and these ionic group must be in a suitable form (acid or base) to function. Variation in pH of medium result in changes of ionic form of the active site, activity of enzyme, hence the reaction rate, affect the maximum reaction rate, Km stability of the enzyme.
3. Variation in pH of medium result in changes of ionic form of the active site.
a) True
b) False
Answer: a
Clarification: Variation in pH of medium result in changes of Ionic form of the active site and activity of enzyme, hence the reaction rate. Variation in pH of medium can also result in changes of the maximum reaction rate, Km stability of the enzyme. Enzyme are active only over small range of pH due to the active site functional group charges (ionic form) and the three dimensional shape of enzyme are pH-dependent.
4. If the substrate contains ionic groups, what happens to the pH of the medium?
a) The pH of medium increases
b) The pH of medium decreases
c) The pH of medium remains same
d) The pH of medium affects the affinity of substrate to enzyme
Answer: d
Clarification: Some cases, the substrate may contain ionic groups, and the pH of medium affects the affinity of substrate to enzyme. This may lead to major changes in the binding of the enzyme to the substrate. This may damage some vital reactions in our body.
5. The rate of enzyme conversion of the substrate will decrease with temperature.
a) True
b) False
Answer: b
Clarification: It will increase. The rate of enzyme conversion of the substrate will increase with temperature up to an optimum. Above this temperature, enzyme activity will decrease as enzyme denatures. Thermal denaturation of the enzyme can occur after a certain point of increased temperature.
6. What is the term given to restriction of enzyme mobility in a fixed space?
a) Enzyme deactivation
b) Enzyme saturation
c) Enzyme activation
d) Enzyme immobilization
Answer: d
Clarification: Immobilized enzymes refers to enzymes being physically confined to or has been localised in a defined region of space. This also helps them to retain their catalytic activities which can be used continuously. The containment of enzyme solution within a confined space for the purpose of retaining and re-using enzyme in processing equipment.
7. What is the product obtained from glucose isomerase?
a) Amino acids
b) High fructose corn syrup
c) Penicillin
d) Acrylamide
Answer: b
Clarification: In corn syrup production the starch is broken down by enzymes. To make, high fructose corn syrup, the corn syrup has to be further broken down or processed by glucose isomerase. This step helps to convert some of the glucose into fructose.
8. Which enzyme gives Acrylamide as a product?
a) Nitrile Hydratase
b) Glucose isomerase
c) Penicillin acylase
d) Beta-Galactosidase
Answer: a
Clarification: Acrlamide is a monomer which is used for production of a lot of substances. It is produced by the addition of water to acrylamide. The catalyst used in this process is nitrile hydratase. This catalyst is difficult to regenerate. Thus we have to use immobilised nitrile hydrates.
9. Catalyst reuse is an advantage of immobilized enzyme systems.
a) True
b) False
Answer: a
Clarification: The enzymes which were immobilized can be reused. Since the enzymes f=don’t get wash off fully, and the active sites are preserved by staking the enzymes all together in a polyester gel. This has advantages of easier operation, easier product separation, and wider choice of reactors.
10. Why is the enzyme solution mixed with a polymeric fluid?
a) To make it more potent
b) Faster reaction
c) More active sites on the surface
d) Solidifies into various forms
Answer: d
Clarification: The enzyme solutions are mixed with a polymeric fluid which will solidify the enzymes into various forms. The solidification depends on application. The polymeric material is semi-permeable. Large is the molecular weight enzymes cannot diffuse out, small substrate and product molecules can.
11. Which one is a matrix for entrapment?
a) Cellulose
b) Polysulfone
c) Nylon
d) Collagen
Answer: d
Clarification: The matrices for entrapment are Ca- alginate, agar, polyacrylamide, collagen. Membrane materials are enzyme solutions which will be confined between thin semipermeable membranes. Membrane materials include nylon, cellulose, polysulfone, polyacrylate.
12. Membrane materials include: Nylon, cellulose, polysulfone and _______________
a) Collagen
b) Polyacrylamide
c) Agar
d) Polyacrylate
Answer: d
Clarification: Membrane materials are the materials by which the membrane will be constructed. The enzyme solution may be confines between thin semi permeable membranes. Membrane materials include nylon, cellulose, polysulfone, polyacrylate.
13. Which membrane configuration is used for separating enzyme from substrate and product solution?
a) Packed column reactor
b) Hollow fibre configuration
c) Fluidized bed reactor
d) Stirred tank reactor
Answer: b
Clarification: Hollow fibre configuration is a very popular arrangement for separating enzyme from substrate and product can be taken out easily. Hollow fibres containing a stationery enzyme solution. Mobile fluid outside fibres containing substrate and products.
14. What is the name of the method used to cross link enzyme molecules with each other using agents such as glutaraldehyde?
a) Cross linking
b) Polyacrylamide
c) Agar
d) Polyacrylate
Answer: a
Clarification: Cross-linking is to cross link enzyme molecules with each other using agents such as glutaraldehyde. Features are similar to covalent bonding. Several methods of crosslinking are combined.