Download LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034
M.Sc. DEGREE EXAMINATION – BIO TECHNOLOGY
SECOND SEMESTER – APRIL 2010
BT 2818 - ENZYMOLOGY & ENZYME TECHNOLOGY
Date & Time: 19/04/2010 / 1:00 - 4:00
Dept. No.
Max. : 100 Marks
PART – A
(20marks)
Answer all the questions
1. Choose the best answer:
(5 x 1 = 5 marks)
(1) David Phillips deduced the structure of
(a) glucose isomerase
(b) pepsin (c) lysozyme (d) lipase
(2) An example of enzyme regulation by covalent modification is
(a) isomerization (b) trypsinization (c) substrate channeling (d) phosphorylation
(3) Trypsinogen is activated by
(a) chymotrypsin
(b) trypsin
(c) pepsin
(d) rennin
(4) The level of which one of the following enzymes will increase in serum following myocardial
damage?
(a) peroxidase (b) lactate dehydrogenase (c) cytochrome oxidase (d) protease
(5) In vitro recombination is also known as
(a) DNA shuffling
(b) homologous recombination
(c) transposition
(d) in vitro replication
II. State whether the following are true or false, if false give reason (5 x 1 = 5 marks)
(6) By placing oppositely charged amino acid residues at a proper distance from the ends of the
α-helices, enzyme stability can be increased.
(7) The transition state formed at the active site is a lower energy state than the reactants.
(8) Lysozyme breaks down the peptidoglycan of bacterial cell walls.
(9) Prostate-specific antigen is a better marker for prostate cancer than prostatic acid
phosphatase.
(10) Calcium alginate immobilizes an enzyme by entrapment.
III. Complete the following:
(5 x 1 = 5 marks)
(11) An enzyme without its bound cofactor is termed as _______.
(12) The energy required by the substrate to be converted to the transition state is known as
________.
(13) Alkaptonuria is caused due to the lack of the enzyme _______.
(14) The small subunit of anthranilate synthase catalyzes the conversion of ______ to ______.
(15) Bio-bleaching of lignin containing fibres is done by the enzyme ______.
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IV. Answer the following, each within 50 words only
(5 x 1 = 5marks)
(16) Distinguish between activity and specific activity of enzymes.
(17) Why does the introduction of sulphide bridges increase enzyme stability?
(18) Mention the role of coenzymes in a catalytic reaction.
(19) Explain the significance of a feedback regulation in a metabolic pathway.
(20) Will a mutation of the His 57 residue affect the activity of serine proteases? Justify answer
with reason/s.
PART – B
(5 x 8 = 40 marks)
Answer any five of the following questions, each within 350 words only.
(21) Give an account of the methods employed for the isolation and purification of enzymes.
(22) Discuss the following:
(i) Allosteric regulation of ATCase
(ii) Irreversible inhibition of enzymes
(23) Briefly explain the different strategies used for the stabilization of industrial enzymes.
(24) Write notes on:
(i) IUBMB nomenclature
(2)
(ii) ‘Induced fit’ theory
(2)
(iii) Activation of trypsinogen
(4)
(25) Explain the following:
(i) Suicide inhibitors
(2)
(ii) Specific activity
(2)
(iii) Enzyme electrode for measuring glucose concentrations (4)
(26) Discuss the following:
(i) Microbial sources of amylase and protease
(ii) Enzyme therapy for cancer
(27) Explain the enzymological relevance of mannosidosis and phenylketonuria.
(28) Describe the expression cloning and molecular screening techniques used in enzyme
discovery.
PART - C
Answer any two of the following, each within 1500 words only (2 x 20 = 40 marks)
(29a) Discuss the enzymes that are clinically relevant for the diagnosis of liver and myocardial
damage and prostate cancer.
OR
(29b) Write notes on:
(i) Different classes of enzymes
(ii) Zymogens
(iii) α ketoacid dehydrogenase complex
(iv) Peptide cleavage and active sites of trypsin, chymotrypsin and elastase.
(30a) Describe the methods used to perform oligonucleotide-directed mutagenesis and random
mutagenesis.
OR
(30b) Explain the following:
(i) Coenzymes
(ii) Stereospecificity and geometric specificity of the substrate
(iii) Coupled reactions
(iii) Effect of substrate concentration and pH on the reaction rate
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