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Discussion 



Charg.^ff: I want to ask Dr. Wilkins a question concerning the nucleoproteins. 

 There is some evidence I believe that the nucleic acids in the cell are mostly present 

 as complicated nucleoproteins, nucleoprotamines and nucleohistones. I believe 

 that Dr. Wilkins has published some evidence about nucleoprotamines which 

 seems to indicate that the structure of DNA is maintained in these protamine 

 complexes. However, there are much more complicated nucleoproteins found, for 

 instance, in bacteria. We have described a deoxyribonucleoprotein from tubercle 

 bacilli which seems to contain one amino acid equivalent per two nucleotides. It is 

 a very peculiar and stable nucleoprotein which cannot be dissociated by strong salt 

 concentrations ; and I am wondering whether anything is known of the X-ray 

 structure of these more highly organized nucleoproteins or, for that matter, whether 

 anything is known about the X-ray structure of the single strand DNA as isolated 

 from a small virus. 



Wilkins : I did not attempt in this talk to get on to the subject of nucleoproteins 

 which is a big and very interesting subject. There is, as Dr. Chargaff points out, 

 good evidence that the nucleic acids do on the whole retain their double helical 



