Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 15: Problem 11

Erythritol is a natural sugar abundant in fruits and fermenting foods. Pathogenic bacterial strains that catabolize erythritol contain four closely spaced genes, all involved in erythritol metabolism. One of the four genes (eryD) encodes a product that represses the expression of the other three genes. Erythritol catabolism is stimulated by erythritol. Present a regulatory model to account for the regulation of erythritol catabolism in such bacterial strains. Does this system appear to be under inducible or repressible control?

Short Answer

Expert verified
Short Answer: The regulatory model for erythritol catabolism in pathogenic bacteria involves four genes. In the absence of erythritol, the product of eryD acts as a repressor, preventing the expression of the other three genes. When erythritol is present, it binds to the eryD product, causing a conformational change that allows the expression of the other genes and inducible control of the catabolic pathway.

Step by step solution

01

Identifying the key components of the regulatory model

Begin by identifying the different elements involved in the regulation of erythritol catabolism - the four genes, the product of eryD, erythritol, and any other relevant factors.
02

Creating a regulatory model for erythritol catabolism

Propose a model that accounts for the observed regulation based on the information provided. In the absence of erythritol, the product of eryD acts as a repressor and binds to the promoter region of the other three genes, preventing their expression (thus the catabolic pathway is "off"). When erythritol is abundant, it binds to the eryD product, causing a conformational change that releases the eryD product from the promoter region of the other genes. This allows the expression of the other three erythritol catabolic genes, and the catabolic pathway is "on".
03

Determine if the system is under inducible or repressible control

Whether a system is inducible or repressible depends on the default state of the pathway (is it initially "on" or "off"). In this case, the presence of erythritol activates the catabolic pathway of erythritol. Therefore, this regulation can be considered an inducible control system.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

A bacterial operon is responsible for the production of the biosynthetic enzymes needed to make the hypothetical amino acid tisophane (tis). The operon is regulated by a separate gene, \(R\) The deletion of \(R\) causes the loss of enzyme synthesis. In the wildtype condition, when tis is present, no enzymes are made; in the absence of tis, the enzymes are made. Mutations in the operator gene \(\left(O^{-}\right)\) result in repression regardless of the presence of tis. Is the operon under positive or negative control? Propose a model for (a) repression of the genes in the presence of tis in wild-type cells and (b) the mutations.

Bacterial sRNAs can bind to mRNAs through complementary binding to regulate gene expression. What determines whether the sRNA/mRNA binding will promote or repress mRNA translation?

Describe the role of attenuation in the regulation of tryptophan biosynthesis.

What properties demonstrate that the lac repressor is a protein? Describe the evidence that it indeed serves as a repressor within the operon system.

Predict the effect on the inducibility of the lac operon of a mutation that disrupts the function of (a) the crp gene, which encodes the CAP protein, and (b) the CAP-binding site within the promoter.
See all solutions

Recommended explanations on Biology Textbooks

Cell Cycle

Read Explanation

Ecological Levels

Read Explanation

Biology Experiments

Read Explanation

Ecology

Read Explanation

Organ Systems

Read Explanation

Chemistry of Life

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free