The Rate and Function of Superoxide Production

These membranes are devoid of cytochrome oxidase, and the alternative 02-utilizing enzymes within them generate superoxide as a primary product. The question arises therefore as to whether superoxide formation could be linked to free energy conservation. A plausible mechanism can be suggested. 

MICHAEL N. BERRY. ANTHONY R. 6RIVELL, and PATRICIA G. WALLACE 

It is tempting to speculate that the univalent reduction of O2, which is the most favorable pathway for O2 reduction, was the primitive pathway 

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