Researchers Expose Hidden Atomic Portrait of Antioxidant Enzyme The mitochondria in human cells depend on manganese superoxide dismutase to keep the amount of harmful reactive oxygen molecules under control. Researchers have now obtained a complete atomic portrait of the enzyme, providing key information about the catalytic mechanism within its active site, situated between the green and blue subunits and the yellow and pink subunits.[ORNL/Jill Hemman] April 7, 2021 The mitochondria in human cells depend on manganese superoxide dismutase to keep the amount of harmful reactive oxygen molecules under control. Researchers have now obtained a complete atomic portrait of the enzyme, providing key information about the catalytic mechanism within its active site, situated between the green and blue subunits and the yellow and pink subunits.[ORNL/Jill Hemman]