Question

chem 103: biochem

need help with answering these questions!!!

6) For the following statements concerning inhibition, use the answers (1 pts each) A) competitive inhibition B) non-competitive C) irreversible and D) not an inhibition a) Which inhibition can be reversed by adding an excess of the substrate? b) In which inhibition does the inhibitor resemble the substrate? c) Inhibitor binds to enzyme at different site than substrate, but it can be removed. d) An example is ethanol as an antidote for methanol poisoning e) Allosteric enzyme inhibitors are examples of what type of inhibition? f) Which usually forms a covalent bond with a side chain in the active site of the enzyme? g) Lead poisoning destroys salt bridges of many enzymes, but it can be removed with h) Sulfa drugs resemble the substrate need by bacteria to make folic acid. What type of inhibitor? EDTA. Lead poisoning is what kind of inhibition? i) Nerve gas is what kind of inhibitor on acetylcholinesterase

Answer 1

ANSWERS

A) :- Competitive inhibitors bind to the active sites of an enzyme and decrease the amount of binding of the substrate or ligand to enzyme

B) :-  In Competitive inhibition, an enzyme can bind substrate or inhibitor but not both. thus the competitive inhibitor resembles the substrate and binds to the active site of the enzyme.

C) :- Noncompetitive inhibitor can bind to an enzyme with or without a substrate at different places at the same time. It changes the conformation of an enzyme as well as its active site, which makes the substrate unable to bind to the enzyme effectively so that the efficiency decreases.

D) :-  Methanol poisoning can be treated with ethanol. This drugs act to reduce the action of alcohol dehydrogenase on methanol by means of competitive inhibition.

E) :-  Non-competitive inhibition involves a molecule binding to a site other than the active site (an allosteric site) .The binding of the inhibitor to the allosteric site causes a conformational change to the enzyme’s active site.

F) :- Irreversible inhibitors are covalently bound to the target enzyme and dissociates very slowly from the enzyme.

G) :-  Lead poisoning is a type of metal poisoning caused by lead in the body. so it is not an inhibition.

H) :-  Competitive inhibition is interruption of a chemical pathway owing to one chemical substance inhibiting the effect of another by competing with it for binding or bonding.  Sulfa drug also act as competitive inhibitors.

For example, sulfanilamide competitively binds to the enzyme in the dihydropteroate synthase (DHPS) active site by mimicking the substrate para-aminobenzoic acid (PABA). This prevents the substrate itself from binding which halts the production of folic acid, an essential nutrient. Bacteria must synthesize folic acid because they do not have a transporter for it. Without folic acid, bacteria cannot grow and divide. Therefore, because of sulfa drugs' competitive inhibition, they are excellent antibacterial agents.

I) :- Nerve gas is an irreversible inhibitor to the enzyme acetylcholinesterase, an enzyme that catalyzes the breakdown of the acetylcholine neurotransmitter into acetate and choline.