RECENT WORK IN AGRICULTURAL SCIENCE 



CHEMISTRY. 



The nucleic acid of the wheat embryo, T. B. Osborne and I. F. Harris {Con- 

 vcctlrvf Sidle Sid. Rpi. 1901, pi. 4, PP- 365-430). — An extended Htudy <if the nucleic 

 acid in tlie wheat embryo, the discovery of which was announced in the report of 

 the station for 1899 (E. S. E., 12, p. 512), is reported. The literature of nucleic acid 

 is reviewed at length, and the methods used in the preparation and analysis of the 

 nucleic acid studied, to which the name tritico-nucleic acid is given, are described 

 in detail. The authors' conclusions are given l)elow in full: 



"(1) The eni])ryo of wheat contains a relatively considerable (piantity of nucleic 

 acid, for which the name tritico-nucleic acid is proposed. About 3.-5 per cent of the 

 commercial embryo meal used in this investigation probaV)ly consisted of tritico- 

 nucleic acid. 



"(2) On keeping, the meal undergoes a change so that the unaltered luicleic acid 

 i.s obtained from it in diminished quantity or not at all. 



"(3) Tritico-nucleic acid has the properties of the true nucleic acids of animal 

 origin, but is less soluble iia water. 



"(4) Its composition corresponds to the formula C4iHg,N„;P,03,. It forms acid 

 salts witli potassium, sodium, or anunonium, which are readily soluble in water with 

 a strongly acid leaction to litmus. In con.sequence of this, it is impossible to make 

 preparations of the acid wholly free from base. The lack of agreement l)etween the 

 analyses of nucleic acids, heretofore published, is largely due to this fact. 



"(5) On hydrolysis with acids, tritico-nucleic acid yields 1 molecule of guanin, 1 

 of adenin, 2 of uracyl, and o of i)entose for every 4 atoms of phosphorous, and also 

 an unidentified Ijasic body. 



"(6) Silver tritico-nucleotinate contains (i atoms of silver for every 4 of phosi)horus, 

 from which the free acid is supposed to contain 6 hydroxy 1 groups. 



"(7) The constitution of tritico-nucleic acid may be represented l)y tlie union of 

 four P(0H)5 groui)s, in which the 4 atoms of phosphorus are united by 3 of oxygen, 

 and all but 6 of the remaining 14 hydroxyls are substituted by the groups named, 

 thus forming a complicated ester of pentahydroxyl phosphoric acid, an acid unknown 

 in the free state, but which Stokes has shown forms stable esters. 



" (8) By a brief hydrolysis with dilute acids, all the guanin and adenin are split off 

 and, at the same time, about one-fourth of the phosphorus appears as orthophosphoric 

 acid. By dilute alkalies, the purin bases are not easily split off, but orthophosphoric 

 acid is rapidly and abundantly formed. 



" (9) After a brief hydrolysis, in acid solution, a complicated phosphoric acid 

 remains which contains no guanin or adenin and only 2 pentose groups for every 3 

 atoms of phosphorus. The composition of its bai'ium salt indicates that it may be 

 formed from the nucleic acid by splitting off 1 of the phosphorus atoms, to which 

 are attached the guanin, adenin, and 1 pentose. 



"(10) Tritico-nucleic acid resembles the nucleic acids of animal origin, in that it 

 contains the purin, pyrimidin and carbohyd-n e groups, together with phosphorus. 

 The purin groups are the same in the animal and vegetable acids, but in the former 

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