The unprecedented growth of interest in protein synthesis among biochemists is both a result of, and has contributed to, our rapidly advancing knowledge of the chemistry and metabolism of the nucleic acids. Over the past two decades, evidence has accumulated which points to an intimate association between cellular nucleic acid and protein synthetic activity. A large number of experiments in bacterial systems have shown that ribonuclease disrupts the cell's protein synthetic machinery and that ribonucleic acid (RNA) can frequently restore it. Studies of bacterial transformation (Hotchkiss, 1957) and the discovery of the autonomous infectivity of tobacco mosaic virus RNA (Gierer and Schramm, 1956) unequivocally established that nucleic acids alone contain the necessary information in their structure to direct the synthesis of new and genetically significant proteins. A large body of information on the fate of C14-amino acids in whole animal demonstrates conclusively that the initial and major site of incorporation of amino acids into protein are the cellular ribonecleoprotein particles (ribosomes). Thus it was clear, before cell-free systems has received much scrutiny, that nucleic acids had some intimate directive role in converting amino acids to protein and that the study of protein synthesis was inseparable from a study of the nucleic acids.


Biochemistry, Biophysics, and Structural Biology