Examine the following theoretical operon (gen) in E. coli which contains structural genes (genC, genB, genA) that are involved in amino acid biosynthesis. The gen operon also includes the gene encoding for the regulator molecule within it. When the amino acid that this operon helps synthesize is present, it binds to the regulator forming a complex which can bind to the operator region. Assume that the regulator molecule only binds to the operator in the presence of the amino acid. Promoter || Operator genC genB gen operon Regulator genA Question 4 Would you consider a null mutation in the regulator gene a gain of function mutation in the gen operon? Why or why not? Question 5 of the operon, assuming the is an abundance of the amino acid in the cell? What would happen if a frame shift mutation occurred in the genA region A. Gain of function B. Loss of function C. Null D. Silent E. Insufficient information

Examine the following theoretical operon (gen) in E. coli which contains structural genes (genC, genB, genA) that are involved in amino acid biosynthesis. The gen operon also includes the gene encoding for the regulator molecule within it. When the amino acid that this operon helps synthesize is present, it binds to the regulator forming a complex which can bind to the operator region. Assume that the regulator molecule only binds to the operator in the presence of the amino acid. Promoter || Operator genC genB gen operon Regulator genA Question 4 Would you consider a null mutation in the regulator gene a gain of function mutation in the gen operon? Why or why not? Question 5 of the operon, assuming the is an abundance of the amino acid in the cell? What would happen if a frame shift mutation occurred in the genA region A. Gain of function B. Loss of function C. Null D. Silent E. Insufficient information

Human Anatomy & Physiology (11th Edition)

11th Edition

ISBN:9780134580999

Author:Elaine N. Marieb, Katja N. Hoehn

Publisher:Elaine N. Marieb, Katja N. Hoehn

Chapter1: The Human Body: An Orientation

Section: Chapter Questions

Problem 1RQ: The correct sequence of levels forming the structural hierarchy is A. (a) organ, organ system,...

See similar textbooks

Similar questions

Given the Table below concerning the lac operon, match the letter with what would be occurring for each scenario. Repressor is bound to the operator, cAMP complex is bound and transcription is prevented. Allolactose is bound to the repressor, cAMP complex is bound, and transcription is prevalent. Allolactose is bound to the repressor, cAMP complex is not assembled, and transcription is slow Repressor is bound to the operator, cAMP complex is not assembled, and transcription is prevented.
Give the levels of Beta-galactosidase activity (high or low or zero) expected for the following partial diploids for the lac operon strains.
. Recall that the trp operon has a special leader sequence (trpL) between the operator and the structural genes that offers attenuation as a mechanism for regulation of gene expression. (A) Draw a diagram of a trpL region of the operon when tryptophan is abundant in the cell.Label the following features: the DNA, 5’ and 3’ polarity of the RNA, the regions 1, 2, 3,and 4 and poly-U of the RNA, the pair of Trp codons (UGG), the ribosome, and RNA-Pol,along with any stem-loop structure that would form under these conditions (B) In the above example, will the rest of the trp operon genes be expressed? Briefly describe your reasoning why or why not (C) The trp codons in region 1 of the trpL gene have mutated to cysteines (UGG to UGC). What will be the effect on attenuation gene regulation of the trp operon? Brieflyexplain your reasoning.
The fictional bacteria Plumbumbacter aurus converts the lead ions to gold ions and uses the resulting electrons to create ATP. aurus has the midas operon which includes the promoter (midasP), the operator (midasO), and eight genes that encode proteins involved in converting lead to gold. The midas operon is regulated by the protein encoded by the midasR gene and the presence of gold ions. When the concentration of gold ions is low, the midas operon is transcribed and the bacteria convert lead into gold. When the concentration of gold is high, the midas operon is off. To better understand regulation of the midas operon, you created P. aurus mutants. The midasR- mutant has a nonfunctional midasR, the midasO- mutant has a nonfunctional midasO, and the midasP-mutant has a nonfunctional midasP. Based on the data below, the midas operon has what type of transcription control? (negative inducible, negative repressible, positive inducible, positive repressible) Strain Produces Gold in…
Mutants were isolated in which the constitutive phenotype of a missense lacl mutation was suppressed. That is, the operon was now inducible. These suppressor mutations mapped to the operon, not to the lacl gene. What could these mutations be?
A marine bacterium is isolated and shown to contain an inducible operon whose genetic products metabolize oil when it is encountered in the environment. Investigation demonstrates that the operon is under positive control and that there is a reg gene whose product interacts with an operator region (o) to regulate the structural genes, designated sg. In an attempt to understand how the operon functions, a constitutive mutant strain and several partial diploid strains were isolated and tested with the results shown in the following table. Host Chromosome F= Factor Phenotype Wild type None Inducible Wild type reg gene from mutant strain Inducible Wild type Operon from mutant strain Constitutive Mutant strain reg gene from wild type Constitutive Draw all possible conclusions about the mutation as well as the nature of regulation of the operon. Is the constitutive mutation in the trans-acting reg element or in the cis-acting o operator element?
1) A. What is the difference between a repressible vs, an inducible operon? B. Using diagrams and words, describe how the Lac Operon is regulated by different levels of lactose and glucose. Be sure to show what’s happening at the molecular level, including the roles of lactose, glucose the repressor protein, cAMP and CAP.
A mutant E. coli strain is isolated which does not ever produce the enzymes β-galactosidase or permease, irrespective of whether lactose is present or absent. If the normal wild-type genotype with respect to the lac operon can be represented as lacI+ lacP+ lacO+ lacZ+ lacY+, give three different mutant genotypes (list all 5 operon components in each case, do not consider partial diploids) which would result in the mutant phenotype described here.
Molecular biology, please explain in detail
consider the fec operon of Staphylococcus madeupiddis, which encodes an iron citrate uptake system. The fec operon promoter, called “Pfec”, is normally off when no regulators are bound to it (like the lac operon promoter). The activator FecA senses iron citrate and brings the appropriate enzyme to Pfec to start fec transcription when iron citrate levels are high. The repressor FecB senses free iron atoms and prevents fec transcription when free iron levels are high by binding to an operator between the promoter and structural genes. Considering the fec operon described above, which mutation would result in the operon being off under all conditions? Deletion of the operator where the repressor FecB binds to the DNA Deletion of the gene encoding the repressor FecB None of these mutations would result in the operon being off under all conditions Deletion of the gene encoding the activator FecA
. 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? Q. A mutation that prevents the binding of the ribosome to the 5′ end of the mRNA 5′ UTR
A constitutive mutation in the lac operon may be of several types. [Note that constitutive means that the structural genes are always expressed, even if lactose is absent.] Name two types of constitutive mutations. Group of answer choices LacY- and LacI- LacOc and LacZ- LacZ- and LacI- LacY- and LacA- LacI- and LacOc