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81.
Kazuo Okamura Kazuyasu Kisaichi Ken-ichiro Takamiya Mitsuo Nishimura 《Archives of microbiology》1984,139(2-3):143-146
A soluble cytochrome, cytochrome c-551 was purified from an aerobic photosynthetic bacterium Erythrobacter species strain OCh 114 (ATCC No. 33942) by ammonium sulfate fractionation, ion-exchange chromatography and gel-filtration. The cytochrome had absorption maxima at 277, 410, and 524–525 nm in the oxidized form, and at 415, 522, and 550.5 nm in the reduced form. At 77 K, the -band of the absorption spectrum of the reduced form split in two at 547 and 549 nm. The millimolar absorption coefficient at 550.5 nm was 26.8 mM-1 cm-1 in the reduced form. This cytochrome was an acidic protein with an isoelectric point of 4.9. Its molecular weight was determined to be 15,000 by gel-filtration on Sephadex G-100 and 14,500 by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The midpoint potential of this cytochrome was +250 mV at pH 7.0. This cytochrome did not bind CO. 相似文献
82.
The extraordinary sensitivity of early erythroid progenitor cells (BFU-e) of normal human bone marrow to tritiated thymidine ([3H]TdR) was studied. While exposure of bone-marrow cells to [3H]TdR for 1 hr resulted in the death of only 40% of the granulocyte-macrophage progenitor cells (CFU-c), 90% of BFU-e were killed. Experiments in which normal bone-marrow cells were mixed with bone-marrow cells which had been exposed to [3H]TdR demonstrated that the excessive killing of BFU-e by [3H]TdR reflected carry-over of the [3H]TdR by the exposed cells. A carry-over effect was not observed for CFU-c, suggesting the presence of a fundamental difference in the metabolism of TdR between CFU-c and BFU-e. There was a suggestion of a carry-over effect regarding two other S-phase-specific agents, hydroxyurea and 1-β-D-arabinofuranosylcytosine. 相似文献
83.
Kazuo Suzuki 《Journal of plant research》1984,97(3):381-396
Observations on native populations of JapaneseEpimedium have revealed that two types of effective pollinators can be recognized. One of the two types, which consists of small bees
(mainlyAndrena spp. andLasioglossum spp.), is characterized by nondiscriminating behavior for collecting pollen and is commonly found inEpimedium. The other type, which comprises medium sizedTetralonia nipponensis and largerBombus diversus queens as main components, showed flower-dependent foraging fidelity associated with nectar-sucking behavior.T. nipponensis with a shorter proboscis pollinated flowers with a shorter spur ofE. trifoliatobinatum and of a part ofE. s sempervirens, while the queen ofB. diversus with a longer proboscis pollinated longer spurred flowers ofE. grandiflorum andE. sempervirens. In the populations of putative hybrid-derivatives which show gradational variations of spur length, bees of the pollencollecting
type pollinated any flower non-discriminately while bees of the nectar-foraging type tended to visit the flowers with spur
lengths corresponding to their proboscis length. These observations suggest that the pollen-collecting bees play an important
role for gene flow among theEpimedium species, and the nectar-foraging bees reinforce the isolation between the species by their selective pollination. Reproductive
isolation between species ofEpimedium is discussed in relation with some practical behavior, such as flying power, of the pollinators. 相似文献
84.
Journal of Plant Research - The arrangement of microfibrils in the wall of epidermal cells in the epicotyl of the azuki bean plant has been observed. The outer and inner tangential walls have a... 相似文献
85.
Intraventricular administration of muscimol (25–100 ng) and intravenously applied aminooxyacetic acid (2.5–10 mg/kg) depressed the crossed extensor reflex response in a dose-dependent manner. The inhibitory effects of both drugs were clearly antagonized by a subconvulsive dose of bicuculline. A very small dose of bicuculline (10–40 μg/kg, i.v.) produced a dose-related enhancement of the crossed extensor reflex response without any sign of convulsion. These results suggest that the crossed extensor reflex response is very sensitive to GABAergic drugs and central GABAergic mechanisms play a role in the modulation of the crossed extensor reflex response. 相似文献
86.
Cell walls of 4-day old rice seedlings were extracted successivelywith ammonium oxalate-oxalic acid, 4% KOH and 24% KOH. A rß-D-glucanpreparation and a xyloglucan preparation were isolated fromthe 4% KOH extract and 24% KOH extract, respectively. Methylationanalysis and enzymic degradation studies of the polysaccharidesshowed that the former was built up predominantly of repeating-oligosaccharideunits of 3-O-rß-cellobiosyl-D-glucose and 3-O-rß-cellotriosyl-D-glucosein a molar ratio of 2.6 : 1.0, and the latter was of repeating-oligosaccharideunits of -D-xylosyl-(16)-rß-D-glucosyl-(14)-[-D-xylosyl-(16)]-rß-D-glucosyl-(14)-D-glucose,-D-xylosyl-(16)-rß-D-glucosyl-(14)-D-glucose and cellobiose.
1 Present address: Department of Botany, Iowa State University,Ames, Iowa 50011, U.S.A. (Received August 29, 1981; Accepted January 12, 1982) 相似文献
87.
Shinozaki Masateru; Hikichi Masayuki; Yoshida Kazuichi; Watanabe Kazuo; Takimoto Atsushi 《Plant & cell physiology》1982,23(3):473-477
Pharbitis nil, strain Violet which had been exposed to high-intensitylight (18,000 lux at 23?C) for 7 days followed by a low-temperaturetreatment (1314?C) for 7 days initiated flower buds evenunder continuous light, but plants given these treatments inreverse order failed to bud. Three days of high-intensity lightat 23?C was most effective in promoting the flower-inducingeffect of the subsequent low-temperature period. Six days oflow temperature following the 3-day high-intensity light periodinduced near-maximum flowering response. DCMU (5?106M) given during the high-intensity light period inhibited flowering,but when given during or after the low-temperature period itwas ineffective. DCMU at the same concentration given before,during or after an inductive 16-hr dark period at 26?C did notinhibit flowering. Sucrose, ATP, NADPH and some other reducingagents tested did not nullify the DCMU effect nor substitutefor the effect of high-intensity light. But, the high-intensitylight effect could be substituted, at least partly, by 5-chlorosalicylicacid, 3,4-dichlorobenzoic acid and some other benzoic acid derivatives,which are highly effective in inducing long-day flowering inthe short-day plant, Lemna paucicostata. (Received October 20, 1981; Accepted February 3, 1982) 相似文献
88.
Tada Mikiro; Shiroishi Masahide; Hasegawa Kiyozo; Suzuki Tetsuya; Iwai Kazuo 《Plant & cell physiology》1982,23(4):607-614
The effect of light on the production of ergosterol and phytoeneand on the composition of carotenoids in Rhodotorula minutawas studied to determine which part of the pathway of carotenoidsynthesis regulated by light. The ergosterol content in the cells was in the range of 3.43.6mg/g dry cells regardless of the presence or absence of illuminationand the light intensity. The phytoene production in the cellswas markedly stimulated by light and was dependent on the lightintensity according to the amount of carotenoid pigments produced.In addition, the ratio of phytoene to carotenoid was in therange of 0.360.44, regardless of the presence or absenceof illumination and the light intensity. The fact that the ratio of carotenoid fractionated on the basisof the functional group involved in each carotenoid to the totalamount of carotenoid was almost constant regardless of the lightintensity suggested that the composition of the carotenoidssynthesized in the cells is not affected by light. It was deduced from these results that light induced the productionof enzyme(s) required for phytoene biosynthesis in Rhodotorulaminuta. (Received November 7, 1981; Accepted March 19, 1982) 相似文献
89.
Two allyl hydroperoxy guaianolide sesquiterpene lactones (peroxyeupahakonin-A and -B) and five new guaianolides (eupahakonin-A and -B, eupahakonenin-A and -B, and eupahakonesin) were isolated from E. chinense and characterized. The allyl hydroperoxy sesquiterpene lactones were characterized by spectral and chemical methods. They were prepared chemically by photosensitized oxygenation of eupahakonin-A. 相似文献
90.
Hideyo Suzuki Kuo-Hsiung Lee Mitsumasa Haruna Toshiyuki Iida Kazuo Ito Huan-Chang Huang 《Phytochemistry》1982,21(7):1824-1825
A new lignan, (+)-aretigenin has been isolated from the roots of Wikstroemia indica (Nan-Ling-Jao-Hua) and identified as 8(R) 8′(S)-4′-hydroxy-3, 4,3′-trimethoxylignan-olid (9, 9′) on the basis of spectral evidence as well as a direct comparison with its enantiomer, (?)-arctigenin. 相似文献