Initiation of protein synthesis in E.
Protein Synthesis Animation Video - YouTube
All tRNA's are similar in structure. The TC arm participates in binding of the charged tRNA to a site on the ribosome where protein synthesis occurs. The DHU (or D) arm is necessary for recognition by the proper aminoacyl tRNA synthase (the enzyme). The acceptor end is at the 3' terminus and ends in the sequence CCA. The anticodon arm consists of seven nucleotides, the sequence of which is read 3' to 5' (opposite convention to the usual 5' to 3').
Protein synthesis Animation - translation initiation in …
In eukaryotes, translation occurs in the cytoplasm, where the ribosomes .Translation is the synthesis of a protein from an mRNA template where the code in the mRNA is converted Transcription vs Translation.
Mechanisms of Protein Synthesis by the Ribosome
After it is synthesized disulfide bonds are formed and the protein folds into its three dimensional state. Some proteins require post-translational modification before becoming fully active. These modifications can include removal of segments using peptidases, addition of phosphate, sugar or lipids to specific amino acids and glycosylation.
Elongation cycle of protein synthesis
The structure and function of the ribosome are fascinatinglycomplex. Two-thirds of the ribosome consist of ribosomal RNA (rRNA),while over 50 ribosomal proteins make up the rest. The geneticinformation is delivered to the ribosome by a messenger RNA(mRNA). Transfer RNAs (tRNAs) are adapter molecules, each equipped withan anticodon to match the codons in the mRNA, and charged with an aminoacid that corresponds to the anticodon as dictated by the geneticcode. The ribosome contains three tRNA-binding sites: A, P, and E (seeelongation cycle box, or watch a ). In addition to mRNA and tRNAs, the ribosomeinteracts with protein factors such as the elongation factors Tu (EF-Tu)and G (EF-G), that are important players in the so-called elongationcycle. The elongation cycle results in the addition of an amino acid tothe nascent peptide chain, and consists of three main steps. In thedecoding step, a ternary complex comprised of an aminoacyl-tRNA(aa-tRNA), EF-Tu, and GTP binds to the ribosome,leading to the recognition of the codon by the anticodon. The followingstep is the peptidyl transfer. Here the peptide chain bound to theP-site tRNA is covalently linked to the amino acid bound to the A-sitetRNA. In the translocation step, the position of the mRNA/tRNA complexshifts by one codon, accompanied by a ratchet-like motion of theribosomal subunits.