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very well what goes on in the stretched fibers in the crystalline structure which 

 has been subjected to X-ray. I am not sure that one should not distinguish be- 

 tween the two parts of their hypothesis; namely, the one that describes the 

 crystallography of what can be measured and the one that postulates this bio- 

 logical model, because I don't know that there is any evidence that nucleic acid 

 looks like that if it has not been subjected to this stretching. I don't know of 

 any evidence except our chemical data, and they could be interpreted different- 



POLLARD: Yes, Wilkins has evidence of that. 



CHARGAFF: That is poor evidence. I think that you do not see the 

 same type of details that you see in the stretched structure. 



POLLARD: Still, it is the only evidence and it is positive. 



CHARGAFF: Yes, but he has too few details to say they are com- 

 patible with such a structure, and I don't think he shows it. 



POLLARD: There is nothing incompatible. 



CHARGAFF: No, but there is quite a distance between something not 

 being incompatible and being true. I mean there is a long way to go. 



CARTER: At any rate, this has served as an extremely useful point 

 of departure for many discussions, and probably about it a considerable amount 

 of solid investigation will be built. 



POLLARD: It has completely licked the problem of biological cell 

 duplication. 



CHARGAFF: I don't share your enthusiasm. There is a need for a 

 peculiar enzyme which enters these huge coils in such a way that you can get 

 duplication. As a matter of fact, it has really taken away some of the fun, be- 

 cause you expose surfaces that are extremely identical. The polyribose back- 

 bone is toward the outside, and you have to go inside to build one chain and the other. 



POLLARD: Start with the ends and work down. 



SPIEGELMAN: That is the way they imagine it; that is, the thing is 

 really unwound. 



CHARGAFF: We call the enzyme "unscrewase. " 



SPIEGELMAN: They have what can be considered as not a completely 

 implausible picture of the function. But I think if Stent's reasoning is correct 

 it is going to simplify matters trennendously because of the possibility of not 

 having to do the whole thing at once but in sections if these breaks are real. 



CHARGAFF: Except I would like to know what these sections really 

 mean. Is each section a gene or what? 



PLATZMAN: Has anyone ever made completely deuterated proteins 

 or nucleic acids? 



CARTER: I don't think so. 



