Genetic Analysis: An Integrated Approach (3rd Edition)
3rd Edition
ISBN: 9780134605173
Author: Mark F. Sanders, John L. Bowman
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 12, Problem 25P
What is the likely effect of each of the following mutations of the trpLregion on attenuation control of trp operon gene transcription? Explain your reasoning.
a. Region
b. Region
c. The entire
d. The start (AUG) codon of the
e. Two
f. Twenty nucleotides are inserted into the trpLregion immediately after the polypeptide stop codon.
g. Ten nucleotides are inserted between regions
h. Two nucleotides are inserted immediately following the polypeptide start codon
i. The entire polypeptide coding sequence of trpLis deleted.
j. The eight uracil nucleotides immediately following region
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
There is Hyaluronic acid synthesis occuring in Group X Strep and it is controlled by an operon with 3 genes, called hasXYZ. Based on the 3-line diagram model,
a. How many ribosome binding sites are there for the protein?
b. How many promoters are there for the genes?
c. How many start codons are there for the protein?
d. How many RNA Polymerase binding locations are there for the genes?
e. How many proteins will be fully functional?
f. How many mRNA strands are made?
2) Attenuation of the trp operon is controlled by the formation of stem-loop structures in the mRNA
of the trpl region. The attenuation function can be disrupted by mutations that alter the sequence
of the repeat DNA regions 1-4 and prevent formation of the RNA stem loops. Describe the most
likely effects on attenuation of each of the following mutation under the conditions specified.
a. Mutation in region 1 and low levels of tryptophan:
b. Mutation in region 2 and low levels of tryptophan:
Mutation in region 2 and moderate levels of tryptophan (low enough to release the
repression but enough to allow the ribosome to NOT pause):
с.
d. Mutation in region 3 and low levels of tryptophan:
е.
Mutation in region 3 and moderate levels of tryptophan (low enough to release the
repression but enough to allow the ribosome to NOT pause):
f.
Mutation in region 4 and low levels of tryptophan:
Which of the following statements is true regarding transcriptional attenuation of the trp operon?
a. The leader peptide encodes a protein that binds to the operator site
b. Translation of the leader peptide stalls when tryptophan levels are high
c. Stalling of the ribosome in region 1 of the leader peptide inhibits formation of the transcriptional terminator
sequence
d. This kind of mechanism can only occur in prokaryotes
e. Both c. and d. are true
Chapter 12 Solutions
Genetic Analysis: An Integrated Approach (3rd Edition)
Ch. 12 - 12.1 Bacterial genomes frequently contain groups...Ch. 12 - Transcriptional regulation of operon gene...Ch. 12 - Why is it essential that bacterial cells be able...Ch. 12 - Identify similarities and differences between an...Ch. 12 - The transcription of -galactosidase and permease...Ch. 12 - 12.6 Is attenuation the product of an allosteric...Ch. 12 - The trpL region contains four repeated DNA...Ch. 12 - The CAP binding site in the lac promoter is the...Ch. 12 - What role does cAMP play in transcription of lac...Ch. 12 - How would a cap- mutation that produces an...
Ch. 12 - Explain the circumstances under which attenuation...Ch. 12 - Consider the transcription of genes of the...Ch. 12 - Describe the lytic and lysogenic life cycles of ...Ch. 12 - 12.14 Define antisense RNA, and describe how it...Ch. 12 - 12.15 Attenuation of trp operon transcription is...Ch. 12 - 12.16 In the lac operon, what are the likely...Ch. 12 - Identify which of the following lac operon haploid...Ch. 12 - Prob. 18PCh. 12 - 12.19 List possible genotypes for lac operon...Ch. 12 - Suppose each of the genotypes you listed in parts...Ch. 12 - 12.21 Four independent mutants (mutants A to D)...Ch. 12 - Suppose the lac operon partial diploid...Ch. 12 - What is a riboswitch? Describe the riboswitch...Ch. 12 - 12.24 A repressible operon system, like the trp...Ch. 12 - 12.25 What is the likely effect of each of the...Ch. 12 - 12.26 Suppose that base substitution mutations...Ch. 12 - 12.27 Two different mutations affect. Mutant...Ch. 12 - How would mutations that inactivate each of the...Ch. 12 - The bacterial insertion sequence IS 10 uses...Ch. 12 - For an E. coli strain with the lac operongenotype...Ch. 12 - 12.31 How could antisense RNA be used as an...Ch. 12 - 12.32 Section describes the function of tRNA...Ch. 12 - The following hypothetical genotypes have genes A,...Ch. 12 - 12.34 Northern blot analysis is performed on...Ch. 12 - Prob. 35PCh. 12 - Prob. 36PCh. 12 - 12.37 The electrophoresis gel shown in part (a) is...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- a. The original constitutive operator mutations in thelac operon were all base changes in o1. Why doyou think mutations in o2 or o3 were not isolated inthese screens?b. Explain how a mutagen that causes small insertions could produce an ocmutation.c. Would a strain with one of the ocmutations described in part (b) and also a lacIS mutation be ableto make β-galactosidase either in the presence orabsence of inducer? Explainarrow_forward4) Suppose you have an E. coli in which the gene that codes for the lac repressor protein has been mutated in such a way that the protein produced can bind to both lactose and DNA (at its specific binding site in the lac operon promoter) simultaneously. What effect, if any, would this have on regulation of expression of the lac operon? Briefly (1 sentence) explain why you would predict the effect or lack of effect this mutation would have.arrow_forwardConsider the lac operon of E. coli. Specifically, explain the following: a. Describe the overall chromosomal structure/organization of the operon, indicating the location and function of the regulatory regions and the structural genes. b. Is lac a catabolic or anabolic pathway? Explain. Is the operon inducible or repressible? Explain. c. Describe the mechanisms involved in negative control & positive controlarrow_forward
- The lactose operon in E. coli comprises two structural genes and three regulatory components.a.State the name of each structural gene and describe its function: b.) State the name of each regulatory component and describe its functionarrow_forwardFor the trp operon, determine whether genes will be expressed (on) or silenced (off) given the following: a. Tryptophan levels are high. b. The trp repressor can no longer bind tryptophan.arrow_forwardTo characterize the promoter of the gadA operon you made a series of deletion mutants removing pieces of the promoter to see what would happen. The results are found below: gad promoter gada gadX gadz 450 +1 lacz activity transcription start site pH 2.0 pH 7.0 A gad promoter beta-galactosidase (lacZ) +++ 450 gad promoter beta galactosidase (lacZ) +++ +++ 300 +1 gad promoter beta galactosidase (lacZ) 150 D gad beta galactosidase (lacz) -450 150 E gad promoter beta-galactosidase (lacZ) -450 -300 Based on these results, what can you conclude about the gad promoter? O a. The promoter is only regulated by repression Ob. The promoter is regulated by a mix of activation and repression O c. The promoter is only regulated by activation O d. The promoter has multiple operators and multiple enhancersarrow_forward
- Listed in parts a through g are some mutations that were found in the 5′ UTR of the trp operon of E. coli. What will the most likely effect of each of these mutations be on the transcription of the trp structural genes? a. A mutation that prevents the binding of the ribosome to the 5′ end of the mRNA 5′ UTR b. A mutation that changes the Trp codons in region 1 of the mRNA 5′ UTR into codons for alanine c. A mutation that creates a stop codon early in region 1 of the mRNA 5′ UTR d. Deletions in region 2 of the mRNA 5′ UTR e. Deletions in region 3 of the mRNA 5′ UTR f. Deletions in region 4 of the mRNA 5′ UTR g. Deletion of the string of adenine nucleotides that follows region 4 in the 5′ UTRarrow_forwardYour investors are concerned that the GasP protein might not be sufficiently produced under normal laboratory conditions. They suggest controlling the transcription of the gasP gene using a chemical that will “trigger” its transcription. a. What type of promoter could be used? b. What chemical will you use to control transcription? c. How does this method of control work?arrow_forwardThe diagram below represents the tryptophan operon with the trp leader mRNA transcript enlarged to represent the AUG translation start codon, two consecutive tryptophan amino acid codons (UGGUGG), and 4 regions (1, 2, 3, and 4) that base pair to form different hairpin-loop structures in the MRNA leader region. Suppose a mutant bacteria has region 4 of the trp operon attenuator region mutated so that it cannot base pair normally. Would the bacteria grow in the absence of the amino acid tryptophan? (hint: in order for bacteria to grow in absence of tryptophan it should be able to synthesize its own tryptophan) Lead&r region trpE trpD trpC trpB trpA DNA 5' 3' Transcription trp leader sequence MRNA UGGUGG 1 (tryptophan codons) AUG UUUUUU No There is insutficient information to answer the question. O Yesarrow_forward
- The diagram below represents the tryptophan operon with the trp leader mRNA transcript enlarged to represent the AUG translation start codon, two consecutive tryptophan amino acid codons (UGGUGG), and 4 regions (1, 2, 3, and 4) that base pair to form different hairpin-loop structures in the mRNA leader region. Suppose a mutant bacteria has region 3 of the trp operon attenuator region mutated so that it cannot base pair normally. Would the bacteria grow in the absence of the amino acid tryptophan? (hint: in order for bacteria to grow in absence of tryptophan it should be able to synthesize its own tryptophan) Leader region trpE trpD trpC trpB trpA DNA 5' 3' Transcription trp leader sequence MRNA AUG UGGUGG UUUUUU 1 2 3 (tryptophan codons) There is insufficient information to answer the question. Yes No O Oarrow_forwardate) DEFINE what is an Operon, and compare and contrast regulation of the LAC Operon and the TRP Operon. When is each turned ON or OFF? A. DRAW each operon in the PRESENCE of its own ligands (signal molecules). B. What controls the activity of the regulatory proteins involved? · Be sure to describe and show both POSITIVE and NEGATIVE regulation where appropriate. C. Explain HOW each type of control system is appropriate for an operon encoding either catabolic or anabolic enzymes.arrow_forwardExplain how the lac operon is regulated under the following conditions. Include the following terms in your answers: Repressor, Operator, RNA polymerase, CAP site, CAP protein, Promoter A. Lactose and glucose are both present. B. Lactose and glucose are both absent. C. Lactose is present and glucose is absent.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Biology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning
Biology (MindTap Course List)
Biology
ISBN:9781337392938
Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. Berg
Publisher:Cengage Learning
QCE Biology: Introduction to Gene Expression; Author: Atomi;https://www.youtube.com/watch?v=a7hydUtCIJk;License: Standard YouTube License, CC-BY