EXPEEIMENT STATION EECOED. 



" Compared with the endosperm proteins of wheat or maize, the protein of 

 rice yields relatively much of each of the basic amino acids, arginin, histidin, 

 and lysin, and comparatively little ammonia and nonamino nitrogen. In its 

 general amino acid make-up it more nearly resembles the majority of the pro- 

 teins of animal tissues than do the proteins of maize or v/heat. This may 

 explain the extensive use of rice as an almost exclusive diet in spite of its low 

 protein content." 



Protein minima for maintenance, T. B. Osboene, L. B. Mendel, et ax. 

 iJour. Biol. Chem., 22 (1915), No. 2, pp. 241-257, fig. 1).—In continuation of 

 previous work (E. S. R., 33, p. 2G2), the authors report the results of feeding 

 experiments with laboratory animals (rats) to determine the minimum amounts 

 of protein required for maintenance. By altering the protein content of the 

 food — including different proportions of lactalbumin, casein, edestin, milk pro- 

 teins, and gliadin in a basal ration supplying an abundance of total calories — 

 it was possible to note how the rats actually responded to the different diets. 



Additional experiments, as yet incomplete, are described in which a limited, 

 weighed amount of food was supplied daily and eaten completely. The effect of 

 the different proteins was studied comparatively by reducing the amount of 

 protein in the ration until growth ceased, or a gradual decline in body weight 

 occurred. The conclusions drawn are in part as follows : 



" Ranges of 7 to 15 mg. of lactalbumin per gram of rat per w^eek represent 

 minima lower than those found for casein, edestin, milk proteins, or gliadin, 

 not to mention the impossibility of maintenance with zein. . . . 



" The different proteins are, with a few exceptions, not so widely divergent 

 in their general amino acid make-up as to lead us to expect wide differences of 

 protein minimum requirement, aside from a few striking examples. In the 

 case of growth with its greater need of protein units, the divergencies of the 

 proteins may manifest themselves more conspicuously than in mere main- 

 tenance. The apparently greater efficiency of lactalbumin, in contrast with the 

 other proteins recorded above, is in harmony with the observation of the 

 apparent economy of this protein as a supplement to deficient rations." 



The need of protein under different conditions, E. Ajbdeehalden, G. Ewaxd, 

 A. FoDOR, and O. Rose {rfliigers Arch. Physiol., 160 (1915), No. 9-10, pp. 511- 

 521; abs. in ZentU. Physiol., 30 (1915), No. 4, p. 181). — Nitrogen metabolism 

 experiments are described with diets consisting exclusively of potatoes or 

 bread with the addition of fat or sugar. The experimental periods were of 5 to 

 8 days' duration. The apparent results of these tests were as follows : 



With a ration of potatoes an ingestion of 4.5 gm. of nitrogen sufficed to attain 

 a nitrogen equilibrium. The consumption of 5.9 gm. of the nitrogen supplied 

 by a ration of Swedish bread was necessary. The amount of available nitrogen 

 thus required was approximately 4 gm. 



The metabolic relationship of the proteins to glucose. — II, Glucose forma- 

 tion from body proteins, N. W. Janney and F. A. Csonka (Jour. Biol. Chem., 

 22 (1915), No. 1, pp. 203-213). — The experiments here reported, which are a 

 continuation of earlier work (E. S. R., 38, p. 261), deal with glucose originating 

 in the metabolism of body protein with special reference to the relative amounts 

 of glucose and nitrogen appearing in the urine of fasting diabetic laboratory 

 animals, i. e., the G : N ratio. The results of the experimental data are sum- 

 marized by the authors as follows: 



" The average urinary G : N ratio in the fasting phlorizin diabetic dog is 

 found to be 3.4 : 1, rather than 3.67 : 1. The body proteins of the dog collectively 

 yield in metabolism about 57.5 per cent of glucose corresponding to the protein 

 G : N ratio 3.6 : 1 ; body proteins of the rabbit about 60 per cent glucose, protein 



