226 EXPERIMENT STATION RECOED. 



Nitrogen assimilation and a new hypothesis of the first stages of protein 

 formation, O. Baudisch {CentU. Bakt. [etc.], 2. AU., 32 {1912), No. 20-25, 

 pp. 520-540). — Coutiniiing previous work (E. g. R., 25, p. 435) the author pre- 

 sents in detail his further studies regarding the steps and agencies in nitrogen 

 assimilation and his hypothesis of a photo-chemical agency in connection there- 

 with. He claims that these studies show results confirmatoiT of the hypothesis. 



Protein synthesis in lower plants, K. Pubiewitsch (Biochem. Ztschr., 38 

 {1912), No. 1-2, in). 1-13). — This is an investigation of the relative availability 

 of difCerent nitrogen compounds for the synthesis of protein. Proceeding upon 

 the assumptions (1) that such synthesis may be judged with a degree of 

 accuracy from the amount of carbon dioxid produced, as a measure of the 

 energy required in the oxidation of the nitrogen compounds, «nd (2) that the 

 less available require the -more energy, the author cultivated Aspergillus niger 

 on a suitable substratum in numerous esiieriments, employing different com- 

 pounds of nitrogen as nitrogen sources. The weight of carbon dioxid evolved 

 in each experiment was compared with the dry weight of mycelium so employed 

 and the ratios so found were then compared. 



The results obtained are said to show that the employment of energy in 

 protein synthesis is least when the amino acids are used as sources of nitrogen. 

 In case of ammonia salts, and particularly of the nitrate, it is considerably 

 greater. From this fact (supported by other observations and inferences) the 

 author concludes that the amino acids are the best sources of nitrogen for 

 protein synthesis. 



A physiological study of nitrate-reducing bacteria, E. B. Feed {CentU. 

 Bakt. [etc.], 2. Abt., 32 {1912), No. 13-19, pp. .',21-U9 pis. 6, figs. 5).— De- 

 tails are given of an extended investigation of 4 bacteria, Bacillus fluorescens 

 liguefaciens, B. pifocyancns, B. denitrificans, and Bacterium hartlebi, in regard 

 to their reducing activity as influenced by such factors as energy supply, 

 presence of nitrites and indicators, and occurrence of certain reactions. 



Potash requirement by the nitrogen bacteria, I. Vogel {Centbl. Bakt. [etc.], 

 2. AM., 32 {1912), No. 13-19, pp. J,ll-.i21). — This is a resumption of worli 

 previously undertaken by the author in connection with M. Gerlach (E. S. R., 

 15, p. 449). It is claimed that the results of the experiments now reported con- 

 firm the conclusions resulting from the earlier series, namely, that a certain 

 development of the bacteria and nitrogen fixation may occur in the absence of 

 potash compounds from the nutrient solution, but that the intensity, both of 

 growth and of nitrogen assimilation, is greatly increased by its presence in 

 suitable quantity. 



Ammonia and nitrates as a nitrogen source for mold fungi, G. E. Ritteb 

 {Ber. Dent. Bot. GescJl., 29 {1911), No. 8, pp. 570^77).— In continuation of a 

 previous study (E. S. R., 22, p. 724), investigatfons wei'e carried out with 

 Cladosporiutn herharum, Mncor racemosus, and M. spinostis, as a result of 

 which the author claims that the nitrate-assimilating fungi are quite commonly 

 able under suitable conditions (in neutral or alkaline culture solutions) to 

 reduce nitrates to nitrites as a first step in such assimilation. This view is 

 held to be supported by the observation that the nitrites can also be utilized 

 as a source of nitrogen. 



Anaerobic decomposition of protein and intramolecular respiration in 

 plants, E. GoDLEWSKi {Bui. Internat. Acad. Sci. Cracovie, CI. Sci. Math, et 

 Nat.. Scr. B, 1911, Nos. 8, pp. 623-704, fig. 1; 9, pp. 705-7i7).— Attempts were 

 made to determine by exi:>eriments with seeds of white and of blue lupines in 

 air-free containers the relation of dependence, if any, which exists between 

 these two processes. The conclusions drawn by the investigator from the final 

 analyses are briefly as follows: 



