Translation

This chapter focuses on translation, the process by which a polypeptide chain is synthesized according to the instructions in an mRNA template molecule; it is the final step in the flow of genetic information from DNA to protein. tRNAs are bifunctional molecules that decipher the genetic information through Watson–Crick pairing interactions with the mRNA, bringing the activated amino acid along for peptide bond formation. The chapter then considers aminoacyl-tRNA synthetases and the structure of the ribosome. Aminoacyl-tRNA synthetases are responsible for the first event in decoding as they determine which of the 40 or so tRNAs in the cell get attached to which amino acids. Meanwhile, the ribosome is the macromolecular ribonucleoprotein machine that coordinates the process of translation through events in two distinct subunits, one primarily responsible for decoding and the other for making peptide bonds. Translation can be divided into multiple stages: initiation, elongation, termination, and ribosome recycling.