The Problem of the Origin of the 

 Proteins 



F. CEDRANGOLO 



Department of Biological Chemistry , University of Naples, Italy 



The problem of the origin of life is, in our opinion, essentially the problem of 

 the formation and of the appearance for the first time on our planet of the giant 

 protein molecule. Once we respond satisfactorily to this problem, I beheve that 

 all the other related problems can be easily and surely solved. 



The proteins must be considered, in fact, like the basal substance of the Hving 

 material. Their molecules are of largest types of molecule (macromolecule) 

 formed by a union of about one hundred simple molecules, that the plants and 

 also the animals (these last, nevertheless, in very limited measure) are able to 

 build, starting from a very simple substance, the plants starting from CO2 and 

 NH3. Also, to day it is possible to produce natural amino acids in the laboratory. 

 Right now about twenty amino acids are knovm and depending on the number, 

 the order, and the proportion with which the amino acids are hnked in the pro- 

 tein molecule, follows the great variation of the animal and vegetable proteins. 

 Using Kossel's [i] very picturesque comparison of the twenty-one letters of the 

 alphabets, united in various number, order, and proportion, they are able to 

 explain an infinite number of thoughts. 



The striking variety of living form, the individuality of every organism, is, 

 essentially, the individuahty of the proteins of which these organisms are com- 

 posed [2]. Any protein is always the permutation and combination of about 

 twenty amino acids which, instead, are always the same. 



Synge [3] has calculated that for one typical protein with a molecular weight 

 of 34,000 containing 288 residues with only twelve different amino acids, it is 

 possible to obtain lo^oo isomers! If only one molecule of each of these isomers 

 existed on Earth, the mass total of the Earth would be lo^so grams ! For- 

 tunately the mass total of Earth is only 10^'^ grams, therefore the existence of 

 all these possible isomers is impossible. 



The problem of the origin of life in the first place is the problem of the origin 

 and the appearance of the amino acids on the Earth, and in the second place the 

 problem of the mechanism with which the amino acids are combined to build 

 the protein macromolecule. 



For this reason the hypothesis of Oparin [4] has produced an exciting glamour; 

 in this hypothesis it is stated that the amino acids made their appearance on the 



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