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Ch. 16 - Regulation of Gene Expression in Bacteria
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All textbooksKlug 12th EditionCh. 16 - Regulation of Gene Expression in BacteriaProblem 21

Chapter 16, Problem 21

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?

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Hello everyone here We have a question that says O. C mutation refers to changes in the D. N. A sequence in the operator region. How does this mutation affect the operation of the black opteron? So the O. C. Meetings have changed D. N. A sequence in the operator region, which prevents the lac repressor protein from binding to it. So because the repressor protein can't bind to it, the operator can't be turned off and the transcription of structural genes will just continue. So our correct answer here is d it prevents the laC repressor from binding to the operator region so it cannot be turned off. Thank you for watching. Bye.
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