SOME RECENT WORK ON PLANT 



OXIDASES 



By W. R. G. ATKINS, M.A., Sc.B., F.I.C., 



Assistant to the Professor of Botany, Trinity College, Dublin 



In the last ten years the attention of plant physiologists has 

 been largely directed to the study of chemical reactions which 

 take place in the individual cells which go to make up tissues. 

 By the application of suitable reagents it has been found possible 

 to examine many of these qualitatively, and to some extent 

 quantitatively. In such researches the formation of precipitates, 

 amorphous or crystalline, and the production of colour reactions 

 within the cells is examined with the aid of the microscope. 

 Frequently it has happened that one and the same tissue has 

 afforded material for workers with entirely different aims in 

 view. For example, researches on carbohydrate formation and 

 solution may be undertaken by one, while another may examine 

 the processes of oxidation occurring in similar cells. Yet though 

 these may seem very different phenomena, they are really closely 

 connected as constituting together important parts of the life 

 of the cell, the elucidation of which in its entirety is the aim of 

 the physiologist. 



Many of these changes can be brought about equally well 

 outside the living cell, though the production of some of them 

 in vitro has as yet baffled the chemist. But the methods by 

 which they are effected in the organism are much more direct, 

 and dispense with the high temperatures and concentrations of 

 strong acids of which the chemist has to make use. Accord- 

 ingly the study of enzymes, as the substances produced by the 

 cells to bring about such specific chemical changes are termed, 

 has become one of the most important branches of biology. 



Numerous researches have been directed to the unravelling 

 of the complicated inter-relations of the mechanism by which 

 the fundamental need of oxygen is supplied, and it has been 

 shown that enzymes termed oxidases are concerned in the 

 utilisation of this gas. 



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