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What does the bla gene in the pGLO plasmid provide?

Ampicillin resistance

What does the GFP gene do when expressed?

Makes colonies glow brilliant green under UV light

What is the role of the araC protein in the pGLO system?

It acts as a regulatory switch that activates GFP expression in the presence of arabinose

What happens to araC when arabinose is present?

Arabinose binds to araC, changing its shape and allowing RNA polymerase to bind at the promoter

What are the three structural genes in the natural arabinose operon?

araB, araA, and araD

What is the function of the PBAD promoter?

It allows RNA polymerase to initiate transcription of the downstream genes when activated

What occurs when arabinose is absent?

araC remains inactive, RNA polymerase cannot bind, and transcription of the GFP gene does not occur

How was the pGLO plasmid engineered?

The araB, araA, and araD genes were replaced with the GFP gene, while keeping the PBAD promoter and araC gene intact

What is the outcome when glucose is present without arabinose?

araC does not activate, GFP is not transcribed, and there is no glow

What is the significance of including ampicillin resistance in the pGLO plasmid?

It serves as a selectable marker to identify successfully transformed bacteria

What does transformation refer to in the context of bacteria?

The process by which a bacterium takes up foreign DNA from its environment

Why do some plates glow while others do not?

GFP is only transcribed when arabinose is present to activate araC; without it, there is no glow

What happens to the transcription of GFP when arabinose is present?

Transcription is activated, leading to the production of GFP and glowing colonies

What is an inducible operon?

An operon that is normally off and is activated by the presence of an inducer, such as arabinose

How does the pGLO system illustrate the operon model?

It demonstrates the regulatory logic of the arabinose operon with araC as the regulator and GFP as the target gene

What is the effect of arabinose on the ara operon in E. coli?

It induces the expression of genes responsible for arabinose metabolism

What is the function of the araC regulatory protein?

To control the expression of genes in response to arabinose availability

What is the relationship between arabinose and the transcription of the GFP gene?

Arabinose must be present for araC to activate and allow transcription of the GFP gene

What is the expected result on a no bacteria control plate?

No growth and no glow, as there are no bacteria to express any genes

What is the role of RNA polymerase in the pGLO system?

To bind to the promoter and initiate transcription of the GFP gene when activated by araC