It would result in the continuous transcription of the operon's genes.
The lac operon is considered an inducible operon because it is activated in the presence of lactose as an inducer molecule. When lactose is present, it binds to the repressor protein, causing it to be released from the operator region and allowing RNA polymerase to transcribe the genes involved in lactose metabolism.
In an inducible operon, the structural genes are transcribed only when an inducer molecule is present. The inducer molecule binds to the repressor protein, causing it to be released from the operator region. This allows the RNA polymerase to bind to the promoter region and initiate transcription of the structural genes.
repressor gene
The molecule that typically causes transcription of an operon is an inducer, which can either activate or repress the operon by binding to a regulatory protein. In the case of an inducible operon like the lac operon in E. coli, lactose acts as an inducer by binding to the repressor protein and preventing it from blocking transcription.
The tryptophan operon is turned off in the presence of tryptophan because tryptophan acts as a corepressor. When tryptophan levels are high, it binds to the trp repressor protein. This trp-repressor complex then binds to the operator region of the operon, preventing RNA polymerase from transcribing the genes involved in tryptophan synthesis.
It binds to the operator.
The lac operon is considered an inducible operon because it is activated in the presence of lactose as an inducer molecule. When lactose is present, it binds to the repressor protein, causing it to be released from the operator region and allowing RNA polymerase to transcribe the genes involved in lactose metabolism.
In an inducible operon, the structural genes are transcribed only when an inducer molecule is present. The inducer molecule binds to the repressor protein, causing it to be released from the operator region. This allows the RNA polymerase to bind to the promoter region and initiate transcription of the structural genes.
The operon segment composed of the gene that codes for a protein repressor is called the regulatory gene. This gene produces the repressor protein that can bind to the operator region of the operon, preventing transcription of the structural genes when the repressor is bound.
An inducible operon, such as the lac operon in E. coli, is a segment of DNA that can be turned on in response to a specific molecule, typically a substrate. In the lac operon, the presence of lactose serves as the inducer, which binds to the repressor protein, causing it to release from the operator region. This allows RNA polymerase to transcribe the structural genes (lacZ, lacY, and lacA) that encode enzymes for lactose metabolism. As a result, the operon is activated only when lactose is available, enabling the cell to efficiently utilize the sugar.
A repressible operon is a type of operon in bacteria where gene expression is usually active but can be turned off when a specific corepressor molecule binds to the repressor protein. This binding causes the repressor to bind to the operator region of the operon, blocking transcription and thus shutting down gene expression. An example of a repressible operon is the trp operon in E. coli, which is involved in tryptophan biosynthesis.
The expression of the tryptophan operon is controlled by a repressor protein that binds to the operator region in the presence of tryptophan. When tryptophan levels are high, the repressor is active and prevents transcription of the operon. When tryptophan levels are low, the repressor is inactive, allowing transcription to occur.
repressor gene
When tryptophan is absent, the repressor protein is in an inactive state, allowing transcription of the trp operon to continue. This is because the repressor protein needs tryptophan to bind to it, enabling it to attach to the operator region and block transcription of the operon.
binding to the trp repressor, causing a conformational change that allows it to bind to the operator region of the trp operon. This blocks RNA polymerase from transcribing the genes, turning off expression of the trp operon.
The molecule that typically causes transcription of an operon is an inducer, which can either activate or repress the operon by binding to a regulatory protein. In the case of an inducible operon like the lac operon in E. coli, lactose acts as an inducer by binding to the repressor protein and preventing it from blocking transcription.
The tryptophan operon is turned off in the presence of tryptophan because tryptophan acts as a corepressor. When tryptophan levels are high, it binds to the trp repressor protein. This trp-repressor complex then binds to the operator region of the operon, preventing RNA polymerase from transcribing the genes involved in tryptophan synthesis.