QUESTION 33 You have added a drug that reduces the activity of the enzyme topoisomerase (gyrase)....

QUESTION 33

You have added a drug that reduces the activity of the enzyme topoisomerase (gyrase). What will happen to the rate of activity of the helicase at the replication fork? Explain your reasoning.

Expert Solution

In order to understand how the addition of drug that reduces the activity of topoisomerase enzyme affects the activity of helicase, let us first give the roles of both enzymes:

Topoisomerase: when the helicase enzyme unwinds the two DNA strands at the replication fork during replication supercoiling of DNA occurs ahead of the replication fork. This enzyme Topoisomerase prevents the DNA double helix ahead of the replication fork from getting too tightly wound as the DNA is opened up. It acts by making temporary nicks in the helix to release the tension, then sealing the nicks to avoid permanent damage.

Helicases: These enzymes opens up the DNA at the replication fork.

Now if a drug is added that reduces the activity of topoisomerase enzyme it will lead to very high supercoiling of the DNA ahead of the replication fork and thus will make it very difficult for helicase to move forward and unwind the DNA during replication. Thus it will reduce activity of helicase and which will ultimately lead to reduced rate of replication and finally seize the replication.

These kinds of drugs are used to cure cancer like Doxorubicin, etc.

gladiator answered 2 years ago

533. You have added a drug that reduces the activity of the enzyme topoisomerase (gyrase). What...

533. You have added a drug that reduces the activity of the enzyme topoisomerase (gyrase). What will happen to the rate of activity of the helicase at the replication fork? Explain your reasoning. 534. You have added a drug that reduces the activity of the enzyme topoisomerase (gyrase). What will happen to the rate of activity of the DNA Polymerase activity on the leading strand? Explain your reasoning. 535. You have added a drug that reduces DNA Ligase activity. What...

If changing the pH of an enzyme solution greatly reduces the activity of that enzyme without...

If changing the pH of an enzyme solution greatly reduces the activity of that enzyme without precipitation, how could you tell in the lab if the result of denaturation or just going to a pH that is just not a good one for the enzyme? And how would a change in pH impact or even stop enzyme function without denaturation? (consider the enzymes that are active in your stomach, such as pepsin)

Protein Denaturation: 1) If changing the pH of an enzyme solution greatly reduces the activity of...

Protein Denaturation: 1) If changing the pH of an enzyme solution greatly reduces the activity of that enzyme without precipitation, how could you tell in the lab if it were the result of denaturation or just going to a pH that is just not a good one for the enzyme? And how would a change in pH impact or even stop enzyme function without denaturation? (Consider the enzymes that are active in your stomach, such as pepsin-discussed in Wikipedia.) 2)...

Laboratory: Enzyme Activity In this laboratory you will examine factors that affect enzyme activity. Catalase is...

Laboratory: Enzyme Activity In this laboratory you will examine factors that affect enzyme activity. Catalase is an enzyme found in the liver that breaks down hydrogen peroxide into water and oxygen gas. It catalyzes the following reaction: H2O2 H2O + O2 You will examine two factors that affect its activity. Part A: The Effect of Temperature on Enzyme Activity Graph the volume of oxygen produced against the temperature of the solution. How is the oxygen production in 30 seconds related...

You are a graduate student testing a new drug (drug G) that reduces cocaine addiction in...

You are a graduate student testing a new drug (drug G) that reduces cocaine addiction in mice. You want to find out what the pharmacological action of drug G is, and you know that it involves monoaminergic signaling, but you don’t know more about it than that. You have found a monoaminergic synapse whose signaling is affected by drug G. You can stimulate the presynaptic neuron at this synapse and record the resulting EPSPs in the postsynaptic neuron. This synapse...

Biochemistry: Enzyme Units Can relative activity be added together? For example, if fraction A has 0.2...

Biochemistry: Enzyme Units Can relative activity be added together? For example, if fraction A has 0.2 U/mL and fraction B has 0.4 U/mL, will combining the two fractions produce a solution with a relative activity of 0.6 U/mL?

You have added a drug that prevents the transfer of electrons from the electron transport chain...

You have added a drug that prevents the transfer of electrons from the electron transport chain of cellular respiration to O2. What would happen to the level of activity in the electron transport chain. Explain your reasoning.

You have added an irreversible inhibitor to a sample of enzyme and substrate. At this point, the reaction has stopped completely?

You have added an irreversible inhibitor to a sample of enzyme and substrate. At this point, the reaction has stopped completely. What can you do to regain the activity of the enzyme? Removing the irreversible inhibitor should get the reaction working again. Adding more substrate will increase the rate of reaction. Adding more inhibitor should get the reaction up to speed again. The enzyme is inactive at this point. New enzyme must be added to regain enzyme activity.

Loss of activity for which enzyme do you believe is the cause of the problem in...

Loss of activity for which enzyme do you believe is the cause of the problem in this child. Briefly explain and also say why it could not have been one of the other enzymes. b) a 2 month old boy is brought to the emergency room in a coma after sleeping through the night and failing to awaken in the morning. He is given intravenous glucose and awakens. Serum levels of pyruvate, lactate and alanine are elevated. A muscle biopsy...

what affect does AgNo3 and Acetone as (inhibitors) have an enzyme activity? are they equally effective...

what affect does AgNo3 and Acetone as (inhibitors) have an enzyme activity? are they equally effective ?

Question