VOL. 10 {1953) NUCLEIC ACID TRANSFER 437 



TABLE IV 



DISTRIBUTION OF 32p FOLLOWING INFECTION OF B/l BY LABELLED T3 



Purine transfer from parental to progeny phage 



Over 95% of the phage phosphorus is located in DNA, and it is therefore desirable 

 to know whether other nucleic acids constituents such as the purine bases are transferred 

 incompletely like the phosphorus. Phages T2, T3 and T4 were grown in purine requiring 

 bacteria in the presence of adenine labelled with ^*C in position 8 (see page 433 et seq.). 

 Paper chromatography shows that in this way both the phage adenine and guanine is 

 labelled with ^*C. Table V presents a series of experiments with the purine labelled 

 phages. They all show incomplete transfer with values not significantly different from 

 those obtained with ^^p ; X3 again seems to transfer a little less than do T2 and T4. 



TABLE V 



DISTRIBUTION OF ^*C FOLLOWING INFECTION OF B/l WITH PURINE LABELLED PHAGE 



Isotope transfer as a function of hurst size 



In experiments with T3 and T4r spontaneous lysis always occurs when the burst 

 size is relatively low. It is known, however, that the r+-phages behave differently, 

 and that lysis can be delayed by a secondary infection (Doermann^^^. At the time of 

 normal lysis the infected cells have not exhausted their capacity for phage production. 

 During the last ten minutes before normal lysis, large amounts of phosphorus-containing 

 phage material is produced in the cells which is not developed into mature phage 

 before lysis (Maal0e and Stent^). After normal lysis, this material cannot be recovered 

 by centrifugation. The incompleteness of the phosphorus and purine transfers might, 

 therefore, be due to our failure to detect parental material transmitted to the immature 

 phage particles formed late in the latent period. 



This hypothesis was tested by infecting bacteria with labelled T4r+-phage and 

 inhibiting lysis artificially by reinfection with unlabelled phage. The burst size in this 

 References p. 442. 



110 



