4-Chloro-7-nitrobenzofurazan: A benzofuran derivative used as a protein reagent since the terminal N-NBD-protein conjugate possesses interesting fluorescence and spectral properties. It has also been used as a covalent inhibitor of both beef heart mitochondrial ATPase and bacterial ATPase.OxadiazolesBenzoxazolesAurovertins: Very toxic and complex pyrone derivatives from the fungus Calcarisporium arbuscula. They bind to and inhibit mitochondrial ATPase, thereby uncoupling oxidative phosphorylation. They are used as biochemical tools.Ficain: A sulfhydryl proteinase with cysteine at the active site from ficus latex. Preferential cleavage is at tyrosine and phenylalanine residues. EC 22.214.171.124.Benzofurans: Compounds that contain a BENZENE ring fused to a furan ring.Proton-Translocating ATPases: Multisubunit enzymes that reversibly synthesize ADENOSINE TRIPHOSPHATE. They are coupled to the transport of protons across a membrane.Chemistry: A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.Chemical Phenomena: The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.Mitochondria, Heart: The mitochondria of the myocardium.Sulfhydryl Compounds: Compounds containing the -SH radical.Lysine: An essential amino acid. It is often added to animal feed.Kinetics: The rate dynamics in chemical or physical systems.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Dinitrochlorobenzene: A skin irritant that may cause dermatitis of both primary and allergic types. Contact sensitization with DNCB has been used as a measure of cellular immunity. DNCB is also used as a reagent for the detection and determination of pyridine compounds.