This compound is produced by a tetrameric enzyme with an iron or manganese active site, which is expressed sevenfold more in termite queens than in workers. A C-terminal SKL (“s-k-l”) sequence localizes proteins to a structure where FAD (“f-a-d”) is a cofactor for generating this compound. Luminol reacts with this compound in ECL reagent to allow imaging of western blots. This compound is produced by a structure that is defective in (*) Zellweger syndrome, (10[1])and it partially names a chemiluminescent enzyme isolated from horseradish. Mitochondrial SOD2 remediates stress from the ETC by generating this compound, which is metabolized in an eponymous organelle that exclusively oxidizes (10[1])branched and very-long-chain fatty acids. For 10 points, catalase breaks down what compound stored in dark bottles into water and oxygen? ■END■