Since VCAA told Victorian teachers that attenuation in the Trp operon was examinable - there has been a lot of discussion about the Trp operon and many questions raised about how attenuation actually works. The answers to some of these questions are elusive. All the videos and texts gloss over them (For example, how many ribosomes are involved? Does the ribosome need to get past the stop codon in the Leader, and the anti-attenuator loop? Are the structural genes translated into a single polypeptide and then cleaved into separate chains, or is each structural gene translated separately - and if so what is the mechanism for that? These are questions that go deeper than VCE students will need (I think) - but they are the sort of questions that keep us awake at night. Well, they keep me awake at night, anyway. This video answers those questions and more. It's detailed - but that's the purpose this time around... to make all those hard-to-make connections.
7 мар 2022
