Biochemical Studies of Virus Reproduction

Despite frequent speculation concerning the mode of action of viruses, few biochemical studies of the virus-host cell relationship have been undertaken, and the sequence of steps in virus multiplication remains largely unknown. Any tenable theory of virus reproduction must consider both the r&e and the fa,te of the original infecting virus particle, and, at present, little evidence is available on this subject. Though the isotopic tracer technique lends itself to a study of this problem through the use of labeled virus, only one early and inconclusive experiment of this nature has been reported (2). In the course of study of virus precursors in the Escherichiu coli Ts bacteriophage system (3-6), procedures were developed for the preparation of Ps2-labeled bacteriophage which made tracer experiments feasible under conditions of controlled infection. The research described below reveals that, while in the course of bacteriophage multiplication a significant amount of the phosphorus of the infecting virus particle appears in the progeny, much of the P is liberated into the medium in a soluble form. The isotopic data, together with observations in bacteriophage genetics (T-lo), indicate that the original infecting virus particle does not survive reproduction.