ON THE MECHANISM OF OXIDASE ACTION 
GB. REED 
(WITH FOUR FIGURES) 
The suggestion was made some years ago by Bacu,' and later 
by KastLe and LoEvENnHART,? that the action of the oxidases de- 
pends on the fact that these bodies have a special aptitude for form- 
ing peroxides; that molecular oxygen in contact with complex 
autoxidizable substances combines with them to form unstable per- 
oxides which in turn can give up their oxygen, in part or completely, 
to any oxidizable substance present in the cell. These changes 
may be represented diagrammatically as follows: (1) A+O,= AO, 
(oxygenase); (2) AO,+2B=A+2BO; or (3) AO.AB=AO+B0; 
and (4) AO,+.A=2A0O; where A is the autoxidizable substance (or 
substances) contained in the cell, which, by uniting with oxygen, 
forms the oxidase AO,. The oxidase, in contact with an oxi- 
dizable substance B, may give up its oxygen in a variety of ways, 
depending upon conditions. All of the oxygen may be absorbed 
by B as in equation (2), in which case A is liberated and may begin 
the cycle again by combining with ‘atmospheric oxygen; but if 
only a part of the oxygen of the oxidase is absorbed, as in equation 
(3), the resulting AO is assumed to be inert and incapable of 
regenerating new oxygenase. Finally, if no combustible sub- 
stances are present, a part of the oxygen of the oxygenase may 
combine with a second A, which thus loses its regenerative power. 
This conception of biological oxidation, originally based upon 
TRAUBE’s peroxide theory of oxidation, finds abundant support in 
many discoveries made during the last 10 years. TRAUBE was of 
the opiriion that hydrogen peroxide is formed as a primary product 
in many, if not in all, oxidation processes, and that through its 
agency oxygen is transferred to the bodies finally undergoing com- 
bustion. ENGLER and his collaborators have been able to show 
* Compt. Rend. Acad. Sci. 124:951-954. 1897. 
* Amer. Chem. Jour. 26:539-566. 1901. 
53] [Botanical Gazette, vol. 62 
