Photosystem I fragments were prepared by digitonin treatment of spinach chloroplasts. The midpoint potential of cytochrome b6 in the fragments is close to 0V, showing a one electron transition. No cytochrome b559 was detectable, neither in difference absorption spectra nor in light-induced absorbance changes. In the absence of added cofactors only cytochrome b6 photoreduction can be observed. T...

The effect of flavone and 7,8-benzoflavone on the metabolism of benzo[a]pyrene to fluorescent phenols by five cytochrome P-450 isozymes obtained from rabbit liver microsomes was determined. Benzo[a]pyrene metabolism was stimulated more than 5-fold by the addition of 600 microM flavone to a reconstituted monooxygenase system consisting of NADPH, cytochrome P-450 reductase, dilauroylphosphatidylc...

This study aimed at evaluating the effect of acetylsalicylic acid (ASA) (150 and 300 mg/kg b.w.) on urinary trichloroethanol and trichloroacetic acid excretion and the liver cytochrome P-450-dependent monooxygenase system (MFO) in rats treated with trichloroethylene (TRI) alone or with xylene (XYL) at a concentration of 4.5 mmol/m air. The study has shown that xylene equally decreased trichloro...

Activation of the phagocyte NADPH oxidase complex requires assembly of the cytosolic factors p47PHOX, p67PHOX, p40PHOX, and Rac with the membrane-bound cytochrome b558. We recently established a direct interaction between p67PHOX and cytochrome b558. In the present study, we show that removal of the C-terminal domain of p67PHOX increased its binding to cytochrome b558. Whereas phosphorylated p4...

A new b-type cytochrome, cytochrome b561 (Murakami, H., Kita, K., Oya, H., and Anraku, Y. (1984) Mol. Gen. Genet. 196, 1-5) was purified to near homogeneity from the cytochrome b561-amplified Escherichia coli K12 strain HM204/pAM5029. The purified cytochrome b561 was a single polypeptide with a molecular weight of 18,000, determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. ...

Quinoprotein (2,7,9-tricarboxy-1H-pyrrolo-[2,3-f]quinoline-4,5-dione quinone form (PQQ)-containing) ethanol dehydrogenase (EDH) from Pseudomonas aeruginosa ATCC 17933 was purified to homogeneity. EDH has an alpha 2 beta 2 configuration and subunits comparable in size to those of methanol dehydrogenase (MDH). Compared with other PQQ-containing dehydrogenases, Ca2+ is rather loosely bound and it ...

Antibodies elicited in rabbits against horse cytochrome c cross-react in varying degree with the cytochromes c of other species. Radioimmunoassay experiments are described in which 23% of the immunoglobulin shown to bind to horse cytochrome c fails to react with beef cytochrome c, and 14% of that bound by beef cytochrome c does not react with rabbit cytochrome c. Studies of hybrid cytochromes, ...

Arima, Kei (University of Tokyo, Tokyo, Japan), and Tetuo Oka. Cyanide resistance in Achromobacter. I. Induced formation of cytochrome a(2) and its role in cyanide-resistant respiration. J. Bacteriol. 90:734-743. 1965.-By following the cytochrome concentrations during the growth cycle and under various conditions (aerobic, aerobic plus KCN, reduced aeration, anaerobic plus NaNO(3)) in Achromoba...

Observations from a number of different experimental approaches have implicated cytochrome pigments in oxidation-reduction reactions resulting from the illumination of photosynthetic tissues (l-6). Possible relationships of these cytochromes to those of the respiratory chain pigments which react with oxygen in the dark have been considered. Vernon (7) isolated a soluble cytochrome in good yield...