214 REPORTS ON INVIlSTlGATlONS AND PROJECTS. 



Osborne, Thomas B^ Connecticut Agricultural Experiment Station, New 

 Haven, Connecticut. Grants Nos. 263 and 349. Application 0/ inetJwds 

 already developed to a comparative study of the tnore important vegetable 

 proteids. (For previous reports see Year Book No. 3, p. iii, and Year 

 Book No. 4, pp. 260-262.) $9,000. 



Abstracts of Reports : Grant No. 26 j {$^,000). — Work under this grant was 

 begun April i, 1905, and concluded April i, 1906. During this time a 

 series of quantitative determinations of glutaminic acid have been made in 

 a large number of carefully purified preparations of vegetable proteins and 

 in some animal proteins. The results of this work have been published in 

 the American Journal of Physiology, March, 1906, vol. xv, page 333. 



The contents of this paper may be summarized as follows : 



Glutaminic acid can be separated more easily in a pure state than any 

 other decomposition product of the proteins. Experiments of our own, as 

 well as a comparison of some of our results with those obtained by others, 

 indicate that this acid can be separated very completely. Properly conducted 

 determinations, therefore, have much value in showing structural differences 

 between various protein bodies and afford the best means at present available 

 for determining the relations of protein preparations and fractional precipita- 

 tions to one another. 



The various proteins examined showed a greater difference in the propor- 

 tion of glutaminic acid which they yielded than has heretofore been found 

 for any other decomposition product of these substances, with the exception 

 of glycocoU, the higher limit for which closely approaches and lower limit 

 falls below that found for glutaminic acid. The largest amount of glu- 

 taminic acid, 37.3 per cent, was found in wheat gliadin. This is the largest 

 proportion of any single decomposition product yet isolated in a pure state 

 from any protein substance. All the proteins examined yielded glutaminic 

 acid. All the seed proteins with one exception gave more than 12 per cent. 



Glutaminic acid is quantitatively the most important protein decomposi- 

 tion product at present known. Nearly all the plant proteins yielded much 

 more glutaminic acid than any of the animal proteins yet examined. Pro- 

 teins which yielded a large proportion of glutaminic acid likewise yielded a 

 relatively large amount of ammonia. A strict numerical relation between 

 the amount of glutaminic acid and ammonia does not exist. It is possible 

 that this relation depends upon the dibasic character of glutaminic acid, 

 since one carboxyl group may be bound in the protein molecule by a 

 polypeptide union, while the other is united with NH2 as an amide. It may 

 be possible to establish closer relations between the dibasic acids and ammonia 

 when we have accurate determinations of the quantity of aspartic acid. 



The method employed for determining glutaminic acid was that of Hlasi- 

 wetz and Habermann. The glutaminic acid was separated as hydrochlo- 



