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991.
Miki Fujioka Nobuo Shimamoto Akira Kawahara Minoru Amano Kazuo Watanabe 《Experimental cell research》1989,181(2):400-408
Scleral fibroblasts of the chick embryo were found to secrete autocrine growth factors. One of the factors was purified from conditioned medium collected from growing-phase cultures of these cells by DEAE-Sepharose column chromatography and following non-denaturing polyacrylamide gel electrophoresis. The specific activity was increased 1100-fold by this purification. The chromatographically purified growth factor was still active after incubation at 95 degrees C, at pH 10 or pH 3, or with glycosidase H, but inactive after incubation with dithiothreitol or trypsin. An active protein having a molecular weight of 32 kDa was found to be the major component of the final preparation. 相似文献
992.
Membrane preparation from the bacteriochlorophyll-containing cells of a facultative methylotroph, Protaminobacter ruber strain NR-1, contained reaction center bacteriochlorophyll similar to those in many species of purple bacteria and contained a few cytochrome species. -Peak of the reduced-minus-oxidized difference spectrum of one of the cytochromes was at 554 nm. The midpoint potential of the cytochrome at pH 7 (Em7) was 350 mV. Two other cytochromes had the same reduced-minus-oxidized difference spectra with a split -band at 557 and 566 nm, but had two different Em7s' of 130 mV and 0 mV.On flash or continuous light the reaction center bacteriochlorophyll and the cytochrome with -peak at 554 nm were reversibly oxidized. Redox titration of the light-induced cytochrome oxidation gave an Em7 value of 356 mV. Under continuous illumination the membrane preparation reversibly took up protons, and formed ATP in the presence of ADP and inorganic phosphate. The ATP formation activity on the bacteriochlorophyll basis was one-third to one-fifth that in chromatophores from Rhodospirillum rubrum under similar experimental conditions. These results clearly indicated that the membrane preparation from P. ruber which contained bacteriochlorophyll had a cyclic photosynthetic electron transfer system and coupled ATP formation activity.Abbreviations Bchl (only in figure legends)
bacteriochlorophyll
- CCCP
carbonylcyanide-m-chlorophenylhydrazone
- Eh
the ambient redox potential
- Em7
the midpoint potential at pH 7
- PMS
N-methylphenazonium methosulfate
- MES
morpholinoethanesulfonic acid
- MOPS
morpholinopropanesulfonic acid 相似文献
993.
James R. Anderson Hika Kuroshima Yuko Hattori Kazuo Fujita 《American journal of primatology》2010,72(8):707-714
Three squirrel monkeys, trained to make a requesting gesture, were tested in the presence of a human assistant whose visual attention varied across trials. When food was available in one dish and an empty dish was nearby, the monkeys pointed overwhelmingly toward the former, regardless of where the assistant was looking. Looking at the assistant while pointing (“monitoring”) peaked when she looked at them and when she attempted to engage them in joint attention. When only one dish was present, the monkeys refrained from gesturing if it was empty and if no assistant was present. They gestured more when the assistant made eye contact with them. Furthermore, when the assistant's focus of attention switched from the dish or the ceiling to the monkeys, the latter resumed pointing and increased their monitoring of the assistant. This is the first demonstration of such flexible use of an intentionally communicative requesting gesture in New World monkeys. Am. J. Primatol. 72:707–714, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
994.
Jun-ichi Kuroyanagi Kazuo Kanai Yuuichi Sugimoto Tetsunori Fujisawa Chikanori Morita Takashi Suzuki Katsuhiro Kawakami Makoto Takemura 《Bioorganic & medicinal chemistry》2010,18(16):5845-5854
Preparations and in vitro antifungal activities of triazolopyridines, imidazopyridines, and a pyrazolopyridine were reported. Among those scaffolds, triazolopyridine was found to be the specific inhibitor of the synthesis of β-1,6-glucan, an essential component of the fungal cell wall, and to show potent antifungal activities against several Candida species. 相似文献
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996.
Nobuhiko Ōkawa Hiroshi Nakayama Keiji Ikeda Keiko Furihata Akira Shimazu Noboru Ōtake 《Bioscience, biotechnology, and biochemistry》2013,77(7):1671-1672
The possibility of using two kinds of sorghum as raw materials in consolidated bioprocessing bioethanol production using Flammulina velutipes was investigated. Enzymatic saccharification of sweet sorghum was not as high as in brown mid-rib (bmr) mutated sorghum, but the amount of ethanol production was higher. Ethanol production from bmr mutated sorghum significantly increased when saccharification enzymes were added to the culture. 相似文献
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