Biochemical Processes in the 

 Simplest Structures 



A. I. OPARIN 



A. N. Bakh Institute of Biochemistry, U.S.S.R. Academy of Sciences, Moscow 



In our view the type of organization peculiar to life could originate only as a 

 result of the evolution of a multimolecular organic system, separated from its 

 environment by a distinct bovmdary, but constantly interacting with this en- 

 vironment in the manner of 'open' systems. Since, as evidenced by a number 

 of features, present-day protoplasm possesses a coacervate structure, the men- 

 tioned systems, which represent the starting point for the evolution leading to 

 the origin of life, could have been coacervate drops. But in contrast to the co- 

 acervates artificially obtained by laboratory methods these drops had to possess 

 a certain pattern of reactions interlinked in time as characteristic for open systems. 

 Moreover, in the course of their evolution the initial systems must gradually 

 have become more complex and elaborate both in space (in regard to their 

 structure), and in time (i.e., in relation to the reaction pattern). 



In a general form these concepts have been discussed in my book The Origin 

 of Life on the Earth (3rd ed., Oliver & Boyd, Edinburgh, 1957). In the present 

 paper only single experimental data are presented obtained within recent time 

 in my laboratory. 



Since initial systems of this type were bound to be destroyed at early stages 

 of the development of Ufe owing to natural selection, and could not have per- 

 sisted up to the present time under natural conditions, we can put the suggested 

 processes of evolution to the test either by gradually increasing the complexity 

 of artificially obtained systems, or by destroying to a certain extent natural 

 protoplasmic structures and making a study of the fragments thus obtained. It 

 is in these two directions that our experiments have been carried out. Of course 

 they can only be regarded as preliminary ones. 



To attain the former aim, we chose, in collaboration with T. Evreïnova, 

 T. A. Shubert, M. N. Nestyuk and G. Larionova artificially prepared coacervate 

 drops. 



To make their organization approach more closely the organization of proto- 

 plasm it was necessary, in the first place, to induce in these drops chemical 

 transformations disturbing their static type of stabiUty. This can most readily 

 be achieved by incorporation, into the coacervate drops, of enzymes which 

 catalyse transformations of substances forming part of these drops. Such in- 

 corporation, in principle, is quite possible, but it can only be realized if certain 

 rules are observed. 



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