High School

Would using a regular promoter from GFP that comes from jellyfish be recognized by bacterial RNA polymerase?

A. Yes
B. No
C. Depends on the bacterial strain
D. Only in the presence of arabinose

Answer :

Final answer:

(b) No. Whether a regular promoter from GFP that comes from jellyfish would be recognized by bacterial RNA polymerase depends on the bacterial strain and if it has been engineered to recognize eukaryotic promoters. Generic eukaryotic promoters are typically not recognized by bacteria, but there are exceptions with engineered strains. In the case of GFP expression, an arabinose-inducible promoter is needed for the addition of arabinose sugar to induce transcription. Hence, (b) is the correct option.

Explanation:

Typically, prokaryotes such as bacteria use different promoters than eukaryotes, such as jellyfish, due to differences in their RNA polymerase enzymes and transcriptional machinery. However, some bacterial strains have been engineered to recognize eukaryotic promoters.

If a scientist were to splice a eukaryotic promoter in front of a bacterial gene and insert it into a bacterial chromosome, the expectation of whether or not the bacterium would transcribe the gene truly depends on whether that particular strain of bacteria has been modified to recognize eukaryotic promoters.

In regards to the expression of GFP, specifically, the addition of arabinose sugar to the growth media would cause RNA polymerase to start transcribing the GFP gene only if an arabinose-inducible promoter is used, which is a specific case different from generic eukaryotic promoters.