In 1968 he received the Nobel Prize. He has continued to work on the very complex problems of understanding how genetic information controls the development and metabolism of living organisms. Horace Freeland Judson. Proteins are very large complex molecules that direct the vast array of chemical reactions that occur within living organisms and which constitute the life of those organisms. Many structural components of organisms are also proteins.
All protein molecules consist of very long chains of simple components called amino acids .
There are just twenty types of amino acid in proteins, but the different orders in which they can be arranged in the chain give rise to many sorts of proteins, with very different biochemical properties. DNA contains the instructions, in coded form, for assembling amino acids into proteins in the right order, but DNA does not control protein production directly. The order of the amino acids in the protein chain is controlled by the order of the bases in the mRNA chain. It takes a codon of three bases to specify one amino acid. Thus UUU is the code 'word' for phenylalanine.