Preface 



Tn 1951 the Section of Biological Chemistry of the International Union of 

 Pure and Applied Chemistry (lUPAC) established a Protein Commission 

 largely for the purpose of investigating the possibility of making available on 

 an international basis a few protein preparations meeting reasonable cri- 

 teria of homogeneity. This task was found to be more difficult than was 

 foreseen, but early in 1957 an insulin preparation, made by the British 

 Insulin Manufacturers, and examined by countercurrent and chromato- 

 graphic methods, was made available. During discussion on a possible 

 extension of this programme, it became apparent that the work of the 

 Commission would be greatly helped and the value of any future plans be 

 better assessed, if the question of homogeneity or 'purity' of proteins could 

 be considered by a special symposium at which many of the leading protein 

 chemists would be present. Financial support by lUPAC was promised in 

 the most generous manner and it was decided to hold such a conference 

 in Paris in the summer of 1957. As the planning of this symposium pro- 

 gressed it became clear that it was not advisable to restrict the subjects to 

 be discussed too closely to questions of immediate relevance to the problem 

 of homogeneity and in the end the programme of the conference was 

 arranged to give an all-round survey of protein chemistry at the present 

 time. 



The lUPAC Symposium on Protein Structure took place in Paris from 

 25 to 29 July 1957 under the general chairmanship of Professor Jean Roche. 

 The Symposium was attended by over 150 protein chemists, but it was felt 

 that a much larger number of people might like to see in print the main 

 papers given in Paris. These are now collected in the present volume, ampli- 

 fied by the contributions of many speakers in the Discussion. Unfortunately 

 it has not been possible to include all the comments which were made and 

 only those which gave new experimental facts directly relevant to the de- 

 fined topics of the Conference are presented. In editing this book contain- 

 ing papers written in three different languages, a considerable degree of 

 latitude has been adopted. The system of quoting literature references has 

 been allowed to vary greatly, and both EngHsh and American spelling has 

 been permitted. 



We would like to thank all those who have helped to make the Paris 

 symposium a success and the publication of this volume possible. Professor 

 Murray Luck, the President of the Section of Biological Chemistry, and 

 other Honorary Officers of lUPAC have given helpful support at all stages. 



