Synthesis of Proteins
Proteins are made from amino acids combined together one after another in a particular sequence by intermolecular dehydration reactions to form the primary structure of the protein. The sequence of amino acids is very important and is different for each protein.
How do these dehydration reactions occur and what determines the sequence in which the amino acids combine with one another? Part of the answer is that there is a "giant enzyme" called a ribosome that catalyzes the reaction that puts the amino acids next to one another and then bonds the amino group of one amino acid to the carboxylic acid group of the next amino acid. It does so by removing one oxygen and two hydrogen atoms from the ends of the two amino acids in order to bond them together using a peptide bond (or an amide bond, if you prefer to call it that). Having done so, it moves on to the other end of the just added amino acid and attaches another another one to it.
This is only part of the answer, however, because the ribosome still needs something to select the amino acids and something to determine the order in which they should be assembled. A different class of compound is involved in carrying out these functions. That class of compound is called nucleic acid, specifically, ribonucleic acid or RNA.
E-mail instructor: Sue Eggling
Clackamas Community College