Codon "n" codon "n+1 合8NA Ribosome movement 6.2 The stages of protein synthesis 1 Before peptide bond formation peptidyl tRNA occupies P site,aminoacyltRNA occupies A site Nascent chain Amino acid for codon n+1 2 Peptide bond fomation involves transfer of polypeptide from peptidyl-tRNA in P site to aminoacyl-tRNA in A site Figure 6.4 The ribosome has two 3 Translocation moves ribosom e one codon; places peptidyl-tRr site;deacylated sites for binding tRNA leaves via E site,A site is empty for next aa-tRNA charged tRNA. 清菜大当 Codon "n+1" Codon "n+2
Figure 6.4 The ribosome has two sites for binding charged tRNA. 6.2 The stages of protein synthesis
6.2 The stages of protein synthesis Aminoacyl-tRNA Polypeptide_is transferred to Translocation moves enters the A site aminoacyl-tRNA peptidyR NA into P site Figure 6.5 Aminoacyl-tRNA enters the A site,receives the polypeptide chain from peptidyl-tRNA,and is transferred into the P site for the enxt cycle of elongation. 情莘大当
Figure 6.5 Aminoacyl-tRNA enters the A site, receives the polypeptide chain from peptidyl-tRNA, and is transferred into the P site for the enxt cycle of elongation. 6.2 The stages of protein synthesis
6.2 The stages of protein synthesis tRNA Figure 6.6 tRNA and E site mRNA move P site A site through the ribosome in the same mRNA direction. 清苇大当
Figure 6.6 tRNA and mRNA move through the ribosome in the same direction. 6.2 The stages of protein synthesis
Initiation 30S subunit on mR NA binding site is joine d by 50S subunit and aminoacyl- tRNA binds 6.2 The stages of protein synthesis Elongation Ribosome moves alon g mRNA and length of protein chain extends by transfer from pepti dyl-tRNA to am inoacyl- Figure 6.7 Protein Temination Polypeptide chain is rele ased from tRNA,an d ribosome dissociate s from mRNA synthesis falls into three stages. 情華大当
Figure 6.7 Protein synthesis falls into three stages. 6.2 The stages of protein synthesis
6.2 The stages of protein synthesis mRNA is translated by triplets Figure 5.9 A ribosome assembles from ● its subunits on mRNA, translates the nucleotide triplets into protein,and then dissociates from the mRNA. 清苇大当
Figure 5.9 A ribosome assembles from its subunits on mRNA, translates the nucleotide triplets into protein, and then dissociates from the mRNA. 6.2 The stages of protein synthesis