Combined--but not individual--microsomal and supernatant fractions obtained from rat brains not only consume oxygen but also provoke emission from added chlorophyll. These results are consistent with literature data (Levis and Mead, J. Biol. Chem. 239, 77 [1964]) for trapping of radioactive 14CO2 following addition of alpha-hydroxy-[1-14C]stearic acid. The most plausible explanation for emission is the interaction of chlorophyll with an alpha-peroxylactone. An intermediary alpha-peroxylactone in alpha-oxidation is consistent with other available data (Salim-Hanna, Campa and Cilento, Photochem. Photobiol. 45, 849 [1987]; Campa, Salim-Hanna and Cilento, Photochem. Photobiol. 49, 349 [1989]) and, on chemical grounds, provides a feasible route to the final products.
