Summary
- Translation is the process of protein synthesis.
- Proteins, or polypeptides, are assembled from amino acid monomers. There are 20 amino acids commonly used for protein synthesis in biological systems. Amino acids are connected via peptide bonds during protein synthesis. Codons in an mRNA specify the order of amino acids in a protein.
- The genetic code is universal, degenerate, and nonoverlapping.
- The ribosome is the molecular machine that catalyzes the peptide bond formation. It is built from a large and small subunit, each of which is built from multiple RNA and protein components.
- tRNA acts as an adaptor, binding to mRNA via codon/anticodon interactions and escorting amino acids to the ribosome. tRNAs contain modified bases and can participate in wobble pairing with codons.
- Translation occurs in three stages: initiation, elongation, and termination. During translation initiation, the small subunit of the ribosome interacts with the ribosome binding site (or 5’ cap). The P site is aligned with the start codon, where an initiator codon binds with a cognate Methionine (or fMet in prokaryotes). During elongation, the ribosome catalyzes peptide bond formation. During termination, release factors release the polypeptide from the ribosome and recycle the ribosome and mRNA.
