LIFESCI 3 Study Guide - Final Guide: Prokaryotic Small Ribosomal Subunit, Prokaryotic Large Ribosomal Subunit, Aminoacyl-Trna
Document Summary
Has 2 subunits these subunits come & go all the time so structure is not static. 1) large subunit = peptidyl transferase center. Where trna anticodon base pairs with mrna codon. Ribosome catalyzes this reaction of a peptide bond formation (acyl linkage) Peptide bond formed at carboxyl end & using amino group to form the bond. Both on a trna bc growing polypeptide chain is always on trna until hydrolysis where we free it bc translation ended. Peptidyl trna = trna with attached polypeptide chain. Aminoacyl-trna = incoming amino acid on trna. Goal: transfer growing chain to trna with incoming amino acid. 3 binding sites for trna for peptidyl transferase activity (ape) Transfers to p-site after it becomes peptidyl trna. Left with empty trna that goes to the e-site. E-site: binding site for trna released after reaction to exit. Prokaryotic ribosomal subunits = 70s subunit bc 30s + 50s is not additive due to shape & size determining sedimentation velocity.
