Introduction 



A. TiSELIUS 



Biochemical Institute, The University of Uppsahr, Sweden 



I think it is very interesting and significant that at this first joint 

 Symposium of the International Union of Biochemistry and the Inter- 

 national Union of Biology you have asked an ex-president of the Inter- 

 national Union of Pure and Applied Chemistry to be in the chair during 

 the first day's discussion of macromolecular structure and function. I have 

 ventured to interpret this as signifying that these problems, so fundamental 

 in biochemistry and biology, can now be discussed also in strictly chemical 

 terms, and it is very gratifying that the host Unions in their activities do 

 not feel themselves limited by barriers between different disciplines, 

 barriers which no longer have any meaning. 



It is very gratifying that among our speakers today we have several to 

 whom we owe some of the most fundamental recent discoveries in this 

 field which have made a symposium with today's subject possible and worth 

 while for discussion. 



Macromolecular substances in biochemistry were until not very long 

 ago confined to what one might call "pre-structural" chemistry. That is 

 to say, one had to content oneself with isolation and characterization, 

 perhaps involving also one or two essential structure details. This is still a 

 very important field of biochemistry, but it is a great advance that today 

 we know that an almost complete structure analysis, also in a strictly 

 chemical sense, can now be made on some typical and particularly im- 

 portant substances of this category. The methods of approach to such 

 structural problems have proved of such general applicability that we have 

 the right to be optimistic about further advances in the near future. It is 

 particularly important just now to observe how different modes and ways 

 of attacking problems of structure among biochemically important 

 macromolecules at last merge together so that information of difi^erent 

 kinds can be utilized in the final attempt to unveil a structure. This is, I 

 understand, what is now happening in the field of protein structure, when 

 X-ray crystallographic analysis data can now be combined with amino 

 acid sequence determinations to work out the details of the structure (e.g. 

 the position of the side chains). Something similar is happening in the 

 nucleic acid field, although the advance there has naturally been slower. 



When discussing biochemical function in relation to structure on a 

 molecular level we are thus now gradually approaching the state in which 

 we can say that we share the problems and the difficulties in some of the 

 most advanced fields of physics and chemistry. The situation makes me 



