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BOOKS AND CURRENT LITERATURE 



ing students than has heretofore been possible. The book comprises eight 

 chapters, in the first of which the author takes up the special chemistry 

 of enzymes and presents an outline of the main groups of these, with 

 discussion of some of the more important in each class. Chapter II is 

 concerned with the physical properties of enzymes. Surface tension is 

 discussed and absorption by colloids and solid neutral media. In the 

 third chapter, activators (co-enzymes), paralysors, and poisons are 

 treated. The author prefers the term activator rather than co-enzyme, 

 for a substance which participates with an enzyme in the acceleration of 

 a reaction. He considers that kinases, which activate zymogens, act 

 essentially as do other activators. 



The remaining five chapters are devoted to the chemistry of enzyme 

 action, treating in order the chemical dynamics of enzyme reaction 

 (with many experimental data), the influence of temperature and of 

 radiation on enzymic reactions, chemical statics of enzyme action, 

 enzymic synthesis and the specificity of enzyme action. An appendix 

 by the translator on Practical Methods and Bertrand's tables for the 

 estimation of sugars complete the work. 



The present volume embodies revision and considerable improvement 

 over the German edition of 1910, and the resvdts of many investigations 

 that have appeared -wathin the last two years have been included. As 

 the author points out, the book is not intended to be a summary of our 

 knowledge of enzymology, but is an attempt to present the more impor- 

 tant facts of that branch of science in their proper relations to general 

 and physical chemistry. This seems to have been accomplished so far 

 as the present limited amount of accurate data on enzyme action will 

 allow. A large number of references add to the value of the work. — 



LoN A. Hawkins. 



