title: Excitation of micelle-solubilized chlorophyll during the peroxidase-catalyzed aerobic oxidation of isonicotinic acid hydrazide.
abstract: Addition of micelle (hexadecyl-trimethylammoniumbromide)-solubilized chlorophyll alpha to the isoniazid/peroxidase/Mn2+/O2 system promotes light emission, identified as chlorophyll fluorescence. Based on O2 consumption, the quantum yield of chlorophyll excitation to the S1 state exceeds 6 X 10(-6). At least part of the excitation has its origin in the conversion of an intermediate--presumably a diazene--to pyridine-4-carboxaldehyde. On the basis of the present and earlier results [K. Zinner, C. C. C. Vidigal, N. Durán, and G. Cilento (1977) Arch. Biochem. Biophys. 180, 452-458], it is inferred that isoniazid, an important chemotherapeutic and also a carcinogenic agent, can lead to a substantial generation of electronically excited states.
mesh_terms: D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000494:pharmacology; D002734:Chlorophyll / Q000378:metabolism*; D000077194:Chlorophyll A; D003102:Colloids; D007538:Isoniazid / Q000378:metabolism*; D007700:Kinetics; D008163:Luminescent Measurements; D008823:Micelles; D010101:Oxygen Consumption / Q000187:drug effects; D010544:Peroxidases / Q000378:metabolism*; D012995:Solubility; D013053:Spectrophotometry; D013113:Spin Labels
chemical_list: D002593:Cetrimonium Compounds; D003102:Colloids; D008823:Micelles; D013113:Spin Labels; D002734:Chlorophyll; D010544:Peroxidases; D007538:Isoniazid; D000077194:Chlorophyll A; D000077286:Cetrimonium