
Concept explainers
(a)
To describe: The effect of increasing the distance between the leader peptide gene and sequence 2 on transcription of the E.coli trp operon.
Introduction:
Transcription attenuation is a mechanism which regulates the translation of a leader peptide by controlling the transcription of structural gene. Trp operon contains two trp codons at attenuator region that forms stem-loop structure. Sequence 1 encodes the leader peptide and sequence 2 is responsible for the constitutive expression.
(b)
To describe: The effect of increasing the distance between sequence 2 and sequence3 on transcription of the E.coli trp operon.
Introduction:
In the presence of tryptophan, occurrence of translation of leader sequences result in blocking the sequence 2. Blocking of sequence 2 followed by transcription of sequence 3 and sequence 4, and formation of attenuator structure.
(c)
To describe: The affect of removing sequence 4 on transcription of the E.colitrp operon.
Introduction:
In the presence of tryptophan, occurrence of translation of leader sequences result in blocking the sequence 2. Blocking of sequence 2 followed by transcription of sequence 3 and sequence 4, and formation of attenuator structure.
(d)
To describe: The effect of changing the two tryptophan (Trp) codons in the leader peptide gene to histidine (His) codons, on transcription of the E.coli trp operon.
Introduction:
Repressible operon represses the expression of structural gene. For example trp-operon have structural gene E, D, C, B and A that are repressed or inactive in the present of tryptophan. As the trp codon forms attenuation structure and make the operon sensitive against the tryptophan.
(e)
To describe: The effect of eliminating the ribosome-binding site for the gene that encodes the leader peptide on transcription of the E.coli trp operon.
Introduction:
Transcription attenuation is a mechanism which regulates the translation of a leader peptide by controlling the transcription of structural gene. Trp operon contains two trp codons at attenuator region that forms stem-loop structure. Sequence 1 encodes the leader peptide and sequence 2 is responsible for the constitutive expression
(f)
To describe: The effect of changing several nucleotides in sequence 3 so that it can base pair with sequence 4 but not with sequence 2, on transcription of the E.coli trp operon.
Introduction:
Transcription attenuation is a mechanism which regulates the translation of a leader peptide by controlling the transcription of structural gene. Trp operon contains two trp codons at attenuator region that forms stem-loop structure. Sequence 1 encodes the leader peptide and sequence 2 is responsible for the constitutive expression and sequence 3 and sequence 4 is responsible for the formation of attenuation structure.

Trending nowThis is a popular solution!

Chapter 28 Solutions
EBK LEHNINGER PRINCIPLES OF BIOCHEMISTR
- what are the different classes and some examples of neuroprotectants that can be used to treat, prevent, or combat neurotoxicity/a neurotoxicant...for example, antioxidants, nutraceuticals, etc.,..?arrow_forwardImagine that aldolase can react with the seven carbon molecule Sedoheptulose-1,7-bisphosphate (below). Use the mechanism to predict the two products generated. Please draw out the stereochemistry in a fischer projection.arrow_forwardSodium borohydride (NaBH4) is a potent inhibitor of aldolase. It is known to ONLY inhibit theenzyme when it is complexed with substrate. Treatment of the enzyme alone has no effect.What is the mechanism for this inhibition? Please draw out the mechanism and show how it inhibits this.arrow_forward
- Show the fate of the proton on the 4-Oxygen molecule of F-1,6-BP. Please include a drawing showing the electron flow that occurs.arrow_forward1. Which one is the major organic product obtained from the following aldol condensation? O NaOH, H₂O heat A B C D Earrow_forwardAn organic chemist ordered the wrong item. She wanted to obtain 1-hydroxy-2-butanone, butinstead ordered 2-hydroxybutyraldehyde. As a good biochemist, show how the organic chemistcould use biological catalysis to make her desired compound. Please show the mechanism by drawing.arrow_forward
- Show the fate of the hydrogen on carbon-2 of glucose. Please draw out the structure using curve arrows to show electron flow.arrow_forward3. Which one of the compounds below is the major product formed by the reaction sequence shown here? CH3 + CH3NO2 NaOH H2, Ni ? nitromethane acetophenone OH OH HO HN- u x x x x Ph A HO -NH2 HO H Ph Ph Ph N- H B Ph NH2 D Earrow_forward4. Only ONE of the five compounds below can be prepared by an aldol condensation in which a single carbonyl compound is treated with base. Which one is it? To solve this problem, reverse the aldol condensation that formed each of these molecules to find out what two molecules came together to make the products. The one in which the two molecules are identical is the answer. Ph Ph ཚིག གནས ག ནཱ ཀ ན ཀནཱ A Ph H B Ph Ph H D Ph. Ph Ph E Harrow_forward
- 5. Which one is the major organic product obtained from the following reaction sequence? First, equimolar amounts of cyclopentanone and LDA are mixed at -78°C. Then propionaldehyde (propanal) is added. Addition of aqueous acid completes the process. LDA, -78°C. 1. 2. H₂O* H A B H 0 D H H Earrow_forward2. Which one is the major organic product obtained from the following reaction? NaOH, H₂O heat A B C D Earrow_forwardCH3CH2CHO + propanal PhCH2CHO 2-phenylacetaldehyde mixture of four products NaOH 10. In the crossed aldol reaction of propanal and 2-phenylacetaldehyde shown above, a mixture of four products will be formed. Which ONE of the compounds below will NOT be formed in this crossed aldol reaction? OH Ph A H OH OH Ph H B OH OH H H H Ph Ph C Ph D Earrow_forward
- BiochemistryBiochemistryISBN:9781319114671Author:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.Publisher:W. H. FreemanLehninger Principles of BiochemistryBiochemistryISBN:9781464126116Author:David L. Nelson, Michael M. CoxPublisher:W. H. FreemanFundamentals of Biochemistry: Life at the Molecul...BiochemistryISBN:9781118918401Author:Donald Voet, Judith G. Voet, Charlotte W. PrattPublisher:WILEY
- BiochemistryBiochemistryISBN:9781305961135Author:Mary K. Campbell, Shawn O. Farrell, Owen M. McDougalPublisher:Cengage LearningBiochemistryBiochemistryISBN:9781305577206Author:Reginald H. Garrett, Charles M. GrishamPublisher:Cengage LearningFundamentals of General, Organic, and Biological ...BiochemistryISBN:9780134015187Author:John E. McMurry, David S. Ballantine, Carl A. Hoeger, Virginia E. PetersonPublisher:PEARSON





