The bacterium Escherichia coli has been genetically engineered to produce human insulin?

Question

The bacterium Escherichia coli has been genetically engineered to produce human insulin. Briefly, explain why the intron sequences, which occur in the human gene sequence for insulin, were omitted when this gene sequence was cloned into Escherichia coli.

Answer 1

Briefly? Ok:

Bacteria don't have introns. They don't have the mechanisms to splice them out as they are prokaryotes. Bacteria can start translating while transcribing as they possess no nucleus. Therefore, there is no chance to remove the introns, which code for many things including regulatory sequences or simply rubbish. Thus, if you do not remove the introns, the bacteria will transcribe them giving you an RNA product that will not produce insulin upon translation.