Study GuideBiochemistry-II–Protein Synthesis1.Fidelity in tRNA AminoacylationWhy Accuracy in Aminoacylation MattersBefore protein synthesis can begin, each tRNA must be attached to thecorrect amino acid.This process is calledaminoacylation.Accuracy here is critical because:•The ribosomedoes not checkwhich amino acid is attached to a tRNA•If a tRNA carries the wrong amino acid, that mistake will be built directly into the protein•Even small errors can produceharmful or nonfunctional proteinsAminoacyl-tRNA SynthetasesAminoacylation is carried out by enzymes calledaminoacyl-tRNA synthetases.Important points:•There are20 different synthetases, one for each amino acid in the genetic code•Each enzyme recognizes:oOne specific amino acidoOne or more specific tRNAs for that amino acidThese enzymes are responsible for maintaining theaccuracy of translation.Step 1: Formation of Aminoacyl AdenylateIn the first step:•The correctamino acidreacts withATP•This forms anaminoacyl adenylate intermediate•Inorganic pyrophosphate (PPi)is releasedPreview Mode
This document has 23 pages. Sign in to access the full document!