2l6 REPORTS ON INVESTIGATIONS AND PROJECTS. 



Since this work was completed Abderhalden and Samuely * have revised 

 their determinations of glutaminic acid in the serum globulin and serum 

 albumin of horse blood, and give as the average of three careful determina- 

 tions in each 8.5 per cent and 7.7 per cent, respectively, instead of 2.2 and 

 1.52 per cent, respectively, which Abderhalden formerly gave.f 



In view of these later figures by Abderhalden, those published earher by 

 him and his colleagues for other animal proteins can not be used as a basis 

 for a quantitative comparison, and in justice to those offering them it should 

 be stated that they were given only as minimal quantities. 



If these later figures are accepted as representing approximately all of the 

 glutaminic acid in these proteins, it would appear that such animal proteins 

 as have been carefully investigated yield similar proportions of glutaminic 

 acid, namely, about 8 to 11 per cent, as may be seen from the following table: 



Glutaminic Acid Yielded by Animal Proteins. 

 Per cent. 



Casein 10.8 Osborne and Gilbert. 



Casein lo.o Fischer. 



Casein io-7 Abderhalden and Pregl. 



Ovalbumin 91 Osborne and Gilbert. 



Ovalbumin 8.0 Abderhalden. 



Seralbumin, horse 7-7 Abderhalden and Samuely. 



Serglobulin, horse 8.5 Do. 



Beef-muscle protein ii.i Osborne and Gilbert. 



Fish-muscle protein 8.9 Do. 



In view of the wide differences in the constitution of the proteins of the 

 different species of seeds, as shown by the determinations of glutaminic acid 

 given in this paper, as well as by the few quantitative determinations of the 

 other decomposition products which have been made, it would seem impor- 

 tant to know definitely whether or not similar differences exist between the 

 proteins of the tissues of different species of animals which serve as food for 

 man, for it is possible that in such differences will be found a logical basis 

 for the use of one form of protein rather than another when deahng with 

 nutrition in various pathological conditions. We hope to be able to follow 

 this work along these lines in the near future. 



The quantitative determinations of the decomposition products of the 

 proteins of the wheat kernel have been completed, and the results have been 

 published under the following title : " The chemistry of the protein bodies 

 of the wheat kernel," Parts II and III, in American Journal of Physiology, 

 1906, XVII, pp. 223 and 231. 



Part II described the methods used in preparing and purifying the large 

 quantities of proteins needed for proper determinations of the decomposition 



* Abderhalden and Samuely. Zeitschrift fiir physiologische Chemie, 1905, XI.VI, p. 194. 

 t Abderhalden. Zeitschrift fiir physiologische Chemie, 1905, xi,iv, p. 22, 1902-1903, 

 XXXVII, p. 484. 



