bio

Sulfide:quinone oxidoreductase

The enzyme that takes electrons off hydrogen sulfide and feeds them into the mitochondrial ubiquinone pool - the very same pool that food-derived electrons enter. It is why sulfide is both poison and fuel: the same molecule, and the only difference is whether this enzyme clears it before the surplus reaches Complex IV. You are carrying it right now; every cell makes a little sulfide deliberately as a signalling molecule, and this is how it cleans up afterwards. The difference between a body that dies in twenty seconds and one that profits is not the machinery but its capacity.