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Wytske de Vries M. I. H. Aleem Anneke Hemrika-Wagner A. H. Stouthamer 《Archives of microbiology》1977,112(3):271-276
Fumarase-free electron particles from Propionibacterium freudenreichii and P. pentosaceum were prepared by discontinuous sucrose gradient centrifugation, and the influence of 2-n-heptyl-4-hydroxy-quinoline-N-oxide (HQNO) and ultraviolet irradiation on the reduction of menaquinone and cytochrome b with l-lactate or glycerol-3-phosphate and the reoxidation by fumarate was studied. In the presence of HQNO the steady state reduction level of menaquinone during fumarate reduction was increased whereas the steady state reduction level of cytochrome b was decreased as compared with the reduction levels measured in the absence of HQNO. The steady state reduction level of menaquinone during electron transport to fumarate was not influenced by ultraviolet irradiation and the steady state reduction level of cytochrome b was decreased at increasing irradiation times. The data indicate that cytochrome b is involved in the electron transport to fumarate.Abbreviations HQNO
2-n-heptyl-4-hydroxyquinoline-N-oxide
- NQNO
2-n-nonyl-4-hydroxyquinoline-N-oxide
Visiting Professor at the Biological Laboratory 相似文献
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Janine F. Bridges Peter C. Millard John F. Woodley 《Biochimica et Biophysica Acta (BBA)/General Subjects》1978,544(2):448-451
The uptake of free and liposome-entrapped 125I-labelled poly(vinylpyrrolidone) was measured in an intestinal sac preparation from adult rats. An an equal concentration of 125I-labelled poly(vinylpyrrolidone), the rate of uptake of the liposome-entrapped material was four times that of the free macromolecule. 相似文献
998.
Pregnant hamsters were administered (SC) prostaglandin or vehicle on the morning of the 4th day of pregnancy. Serum progesterone was significantly depressed (p<.01) at 0.5, 2, and 6 hours after treatment with 100 μg PGF2α. Serum progesterone levels were unchanged 2 hours and 6 hours after treatment with 100 μg PGF2β and 2 hours after treatment with 1 mg PGF2β. Progesterone levels were depressed to less than 1 ng/ml 6 hours after treatment with 1 mg PGF2β. The specific uptake of 3H-PGF2α in whole hamster corpora lutea was significantly depressed 2 hours and 6 hours following 100 μg PGF2α treatment. A 15% depression in specific uptake occurred 0.5 hour post-treatment. Treatment with 100 μg PGF2β resulted in no change. Administration of 1 mg PGF2β resulted in depressed 3H-PGF2α uptake at both 2 and 6 hours post-treatment.Prostacyclin (PGI2) treatment resulted in no change in either 3H-PGF2α specific uptake or serum progesterone 2 hours after 100 μg treatment SC. These parameters were both reduced approximately 30% 6 hours post-treatment. Treatment with 6-keto-PGF1α resulted in a complete lack of measurable 3H-PGF2α uptake and serum progesterone levels less than 1 ng/ml at both 2 and 6 hours after treatment with 1 mg SC. 相似文献
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