Question

You transform an E. coli bacterium with the pGLO plasmid. After growing the +pGLO bacteria on an LB+Ampicillin+Arabinose plate, you see distinct colonies form after 16 hours. You check these colonies under the UV light and see that they are glowing a bright fluorescent green color. If you use a sterile loop and inoculate a new plate with LB+Ampicillin (coated on them, as usual) with these transformed E. coli will you see any growth? If there is growth, will it glow? OA. Yes, we will see growth. Yes, they will glow. B. Yes, we will see growth. No, they will not glow. C. No, we will not see any growth. No, they will not glow. O D. No, we will not see any growth. Yes, they will glow.

Answer 1

Answer:

B. Yes, we will see growth. No, they will not glow.

Explanation:

pGLO plasmid has two notable reporter genes. First gene codes for enzyme beta lactamase which confers resistance against beta lactam antibiotics like ampicillin. Second gene codes for a green fluorescent protein which makes the bacterial colonies glow in UV light. This gene is inserted in an arabinose operon which means that arabinose is mandatory for its expression. Hence, it will only make the colony glow when media is supplemented with arabinose.  

In the given situation, E.coli bacterium has been successfully transformed with pGLO plasmid and hence it is able to grow on LB+Ampicillin+Arabinose plate and also glows in UV light. When it is grown on only LB+Ampicillin plate, it is still able to grow because the gene for ampicillin resistance is in the plasmid. However despite the presence of GFP gene it is not able to glow because there is no arabinose in media to start the operon. Thus GFP gene is not expressed and the colonies do not glow in UV light.