MIMM 211 Lecture Notes - Lecture 14: Start Codon, Transfer Rna, Genetic Code

• School: McGill University
• Department: Microbiology & Immunology
• Course: MIMM 211
• Professor: Benoit Cousineau

Document Summary

Here, the 5" end is on the left (be careful bc it will not always be drawn the same) The aa is loaded onto the last a of the cca. The anticodon triplet is complementary to the codon triplet on the mrna. The different aas are attached to their corresponding trna at the 3" end by aminoacyl-trna synthetases. All of the s #s are sedimentation factors, therefore, the bigger the number, the larger the mass. The rrnas present fold, associate and then become the scaffolding on which the other pp chains bind. We will see why having a two part machine is important in the initiation step. Note that most of the time in bacterial cells, the start codon will be aug (methionine) but sometimes it can be. A nucleophilic attack that leads to the transfer of the growing chain of peptides from the p site trna to the a site trna.