142 



G. E. GAGE. Biology and Chemistry of Nitroso-Bacteria. 



(Centr. Bakt. Par., 1910, ii, 27, 7-48). Journ. of Chem. Soc. 

 Abstr., June 1910. 



The weakest strains of Pseudomonas radicicola can be made cap- 

 able of fixing considerable amounts of nitrogen by constantly grow- 

 ing .on non-nitrogenous media. As regards the utilisation of sugar, 

 it was found that maltase gives the best results. With carbohy- 

 drates containing less than five carbon atoms gum is not produced. 

 In old cultures, especially on solid media, Pseudomonas radicicola^ 

 develops a membrane which appears cell-like in structure, but does 

 not give cellulose and starch reactions. 



When inoculated from such cultures into artificial culture solu- 

 tions, it may be capable of producing considerable amounts of ni- 

 trites and nitrates. There is, at present, no evidence that nitrates 

 are produced without nitrite production. 



H. M. VERNON. Intracellular Enzymes. London, John Murray, 

 Albemarle Street, W., 1908, pp. xi-234. 



The following is from the preface of this book: 

 "The progress of research renders it more and more evident 

 that the cellular protoplasm of all living organisms is made up very 

 largely of ferments or enzymes, and that many or most of its pro- 

 perties are dependent upon their activities. The literature dealing 

 with these intracellular enzymes is scattered and somewhat frag- 

 mentary, and comparatively little of it has as yet found its way 

 into text-books. This is partly because of its recent origin, tor 

 reference to the authorities cited at the foot of the pages in this book 

 will show that almost the whole of the research work described has 

 been carried out during the course of the last decade. If such 

 rapid rate of progress be continued in the future, the subject of 

 intracellular enzymes bids fair to become, if it has not already be- 

 come, one of the most important branches of bio-chemistry, for 

 it alone seems to offer a clue to the solution of the most funda- 

 mental of all biological problems, the nature and constitution of 

 protoplasm." 



