Session VI! DISCUSSION 



Prof. M. Calvin (U.S.A.), as president of the closing session, gave a short resume of 

 the basic problems which had been considered in the previous sessions and invited the 

 participants in the Symposium to contribute to a general discussion on the whole pro- 

 gramme of the Symposium. 



The following took part in the general discussion: S. Fox (U.S.A.), S. Scher (U.S.A.), 

 J. D. Bemal (Great Britain), D. I. Sapozhnikov (U.S.S.R.), K. Mothes (German Demo- 

 cratic Republic), E. Chargaflf (U.S.A.), G. Schramm (Federal German RepubUc), K. Felix 

 (Federal German Republic), A. M. Goldovskii (U.S.S.R.), T. N. Godnev (U.S.S.R.), 

 M. Calvin (U.S.A.), A. E. Braunshteïn (U.S.S.R.), A. G. Pasynskii (U.S.S.R.), S. Miller 

 (U.S.A.), N. Horowitz (U.S.A.), L. Pauling (U.S.A.), A. I. Oparin (U.S.S.R.) and 

 M. Florkin (Belgivmi). Below is a transcript of the contributions. 



The contributors unanimously remarked on the extreme interest of the Symposium 

 and the outstanding importance of Academician A. I. Oparin's theory which provides 

 the possibility of proceeding to the formulation and solution of a number of questions 

 concerned with the problem of the origin of life on the Earth. They thanked the Inter- 

 national Union of Biochemistry, the Academy of Sciences of the U.S.S.R. and the 

 Organizing Committee for caUing the Symposium, for its good organization and for the 

 hospitality extended to the foreign visitors. 



S. Fox: It is necessary to stress the possible part played by a high environmental tem- 

 perature in facilitating the process of autotrophic synthesis in the earliest living systems. 

 In this connection we should direct attention to the importance of the investigations of 

 the biochemical processes in contemporary thermophilic organisms inhabiting hot 

 springs. 



At the beginning of this month I visited Cerro Pietro, a volcanic region in Mexico, 

 and was struck by the similarity of the flora of the hot springs there to that of the hot 

 springs in the Yellowstone Park. Dr Scher informed me that the same is true of those 

 in New Zealand. At the present moment I cannot yet tell what is the significance of this 

 parallelism, but I expect that it is great and I hope that the biochemistry and biology of 

 the organisms of hot springs will receive thorough study. Further details arc given in 

 an article inj. ehem. Educ, 34, 472, 1957. 



S. Scher: I listened with interest to Prof. Fox's remarks. It must be pointed out that 

 a medium with a high osmotic pressure is more effective for supporting life at high 

 temperatures. 



J. D. Bernal: We have more or less reached agreement about the formation of the 

 first organic compounds on the Earth and the conditions under which anaerobic and 

 aerobic metabolism arose. But the intermediate stages between these two are still poorly 

 studied and neither the chemical nor biochemical laws applying to them are known. 



In giving a definition of life we must take into account whether the medium in which 

 separate components interacted could promote the origin of metabolism and also whether 

 coacervate drops (of the type discussed by Oparin) favourable to metabolic processes 

 could develop within this medium. 



The models which have been discussed here (gelatin and gum arabic) were not made 

 with substances which could have been primary in the process of emergence of life, such 

 as, for instance, polysaccharides. It would be a good thing if further investigations could 

 be carried out using these substances. 



D. I. Sapozhnikov: I cannot agree with the opinion that autotrophic organisms were 

 primary. The idea that Ufe first arose in hot springs was first put forward by V. L. Komarov 



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