Concept explainers
. Seven E. coli mutants were isolated. The activity of
the enzyme β-galactosidase produced by cells containing each mutation alone or in combination with other
mutations was measured when the cells were grown in
medium with different carbon sources.
Lactose +
Glycerol Lactose Glucose
Wild type 0 1000 10
Mutant 1 0 10 10
Mutant 2 0 10 10
Mutant 3 0 0 0
Mutant 4 0 0 0
Mutant 5 1000 1000 10
Mutant 6 1000 1000 10
Mutant 7 0 1000 10
F′ lac from mutant 0 1000 10
1/ mutant 3
F′ lac from mutant 0 10 10
2/ mutant 3
Mutants 3 + 7 0 1000 10
Mutants 4 + 7 0 0 0
Mutants 5 + 7 0 1000 10
Mutants 6 + 7 1000 1000 10
Assume that each of the seven mutations is one and
only one of the genetic lesions in the following list.
Identify the type of alteration each mutation represents.
a. superrepressor
b. operator deletion
c. nonsense (amber) suppressor tRNA gene (assume
that the suppressor tRNA is 100% efficient in suppressing amber mutations)
d. defective CRP–cAMP binding site
e. nonsense (amber) mutation in the β-galactosidase gene
f. nonsense (amber) mutation in the repressor gene
g. defective crp gene (encoding the CRP protein)
Trending nowThis is a popular solution!
Step by stepSolved in 4 steps
- Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSONBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxAnatomy & PhysiologyBiologyISBN:9781259398629Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa StouterPublisher:Mcgraw Hill Education,
- Molecular Biology of the Cell (Sixth Edition)BiologyISBN:9780815344322Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter WalterPublisher:W. W. Norton & CompanyLaboratory Manual For Human Anatomy & PhysiologyBiologyISBN:9781260159363Author:Martin, Terry R., Prentice-craver, CynthiaPublisher:McGraw-Hill Publishing Co.Inquiry Into Life (16th Edition)BiologyISBN:9781260231700Author:Sylvia S. Mader, Michael WindelspechtPublisher:McGraw Hill Education