BIOL 1100 Lecture Notes - Lecture 24: Aminoacyl-Trna, Start Codon, Ribozyme
Document Summary
Start codons are 3 (64 types of combinations) Separated into two units: the small subunit holds the mrna in place during translation, the large subunit is where peptide bonds form. During translation, three distinct trnas line up within the ribosome. Initiation phase begins with aug start codon: preceded by a ribosome binding site (shine-dalgarno sequence) which is complementary to a section of one rrna in small subunit. Interaction between small subunit and mrna is mediated by initiation factors. At the start of the elongation phase, the initiator trna is in the p site (e and a sites are empty) An aminoacyl trna binds to the codon in the a site via base pairing between anticodon and codon. Peptide bonds form between amino acids on trnas in the p and a sites. After peptide bond formation, the polypeptide on the trna in the p site is transferred to the trna in the a site.
