Choose the incorrect statements from the following:
A. Statins produced by the yeast Monascus purpureus lower blood cholesterol by competitively inhibiting the enzyme responsible for synthesis of cholesterol.
B. Bottled fruit juices are clarified by the use of pectinases and lipases.
C. Streptokinase produced by the bacterium Streptococcus and modified by genetic engineering is used as a ‘clot buster’ in patients who have undergone myocardial infarction.
D. Cyclosporin A, used as an immunosuppressive agent in organ-transplant patients, is produced by the bacterium Trichoderma polysporum.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → B and D only
Microbes give us many useful enzymes and bioactive molecules. To judge such statements, remember three things for each product: the microbe, whether it is a bacterium, fungus or yeast, and what the product does.
A. Statins produced by the yeast Monascus purpureus lower blood cholesterol by competitively inhibiting the enzyme responsible for synthesis of cholesterol. — True. Statins are made by the yeast Monascus purpureus and are sold as blood-cholesterol lowering agents. They compete with the substrate for the enzyme that makes cholesterol, so less cholesterol is made.
B. Bottled fruit juices are clarified by the use of pectinases and lipases. — False. Bottled juices are clarified by pectinases and proteases. Lipases are used in detergent formulations to remove oily stains from laundry.
C. Streptokinase produced by the bacterium Streptococcus and modified by genetic engineering is used as a ‘clot buster’ in patients who have undergone myocardial infarction. — True. Streptokinase removes clots from the blood vessels of patients who have had myocardial infarction, which leads to heart attack.
D. Cyclosporin A, used as an immunosuppressive agent in organ-transplant patients, is produced by the bacterium Trichoderma polysporum. — False. The use is right, but Trichoderma polysporum is a fungus, not a bacterium.
So the incorrect statements are B and D.
NCERT Extract:
Chemicals, Enzymes and other Bioactive Molecules – “… Lipases are used in detergent formulations and are helpful in removing oily stains from the laundry. You must have noticed that bottled fruit juices bought from the market are clearer as compared to those made at home. This is because the bottled juices are clarified by the use of pectinases and proteases. Streptokinase produced by the bacterium Streptococcus and modified by genetic engineering is used as a ‘clot buster’ for removing clots from the blood vessels of patients who have undergone myocardial infarction leading to heart attack.
Another bioactive molecule, cyclosporin A, that is used as an immunosuppressive agent in organ-transplant patients, is produced by the fungus Trichoderma polysporum. Statins produced by the yeast Monascus purpureus have been commercialised as blood-cholesterol lowering agents. It acts by competitively inhibiting the enzyme responsible for synthesis of cholesterol.”