Question

QUESTION 10 A geneticist has discovered a mutant E. coli strain that is normal at 37°C. However, when grown at 40°C, all functional protein synthesis stops. The geneticist finds out that at 40°C ribosomes are associated with mRNA, but only a single charged tRNA is associated with the ribosome. What is the most likely problem with this E. coli strain? O mutant peptidyl transferase O mutant Shine-Dalgarno sequences O mutant EF-G O mutant EF-Tu mutant 1F3 factors O mutant RF1

Answer 1

during translation initiation the initiation factors IF1 and IF3 associates with the 30S subunit, it then binds to the ribosome binding site in the mRNA then initiator tRNA bound to the IF2 binds to the mRNA then large subunit of the ribosome binds, then all the initiation factors are released, here the large subunit cannot bind, this is due to the mutation in the initiation factor, it is not released from the ribosome, so the answer is mutant IF3 factors.