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31.
Michio Masuda John A. West Yukimasa Ohno Munenao Kurogi 《Journal of plant research》1984,97(1):107-125
Samples of theGigartina pacifica-ochotensis complex were collected at 21 localities around Hokkaido and northern Honshu. The carpospore and blade tip cultures showed 3 reproductive patterns. (1) 237 (86.8%) of the 273 cultured isolates derived from single plants have a direct type of life history. (2) 29 (10.6%) isolates exhibited a heteromorphic type with the alternation of foliose gametophytes and crustose tetrasporophytes. (3) 7 (2.6%) isolates showed a mixed pattern in which carposporelings developed intoPetrocelis-like crusts, basal discs with uprightGigartina blades, or chimera-like discs with compositePetrocelis-Gigartina anatomy. CulturedGigartina blades derived from bothG. pacifica andG. ochotensis were similar in morphology. In 18 cultures from 5 localitiesPetrocelis tetraspores developed into dioeciousGigartina gametophytes. A single tetrasporeling grew into aGigartina plant that reproduced directly. In hybridization experiments with 8 male and 14 female isolates from 4 localities on Hokkaido 85 (78.0%) of 109 were positive. On the basis of these and earlier studies it is concluded that a single species is present in northern Japan:G. pacifica Kjellm. has priority overG. ochotensis (Rupr.) Rupr. ex Yendo. 相似文献
32.
Hiromasa Kijima Taisaku Amakawa Michio Nakashima Hiromichi Morita 《Journal of insect physiology》1977,23(4):469-479
Previously reported PII-type α-glucosidase located in the precipitate of the labellar homogenate of the blowfly Phormia regina was solubilized by sodium deoxycholate (DOC) and further separated into three isozymes with different molecular weight: PII-M (mol. wt 9 × 104). PII-D (mol. wt 2 × 105) and PII-T (mol. wt 8 × 105) by molecular sieve chromatography on Biogel P-300 or Ultragel AcA-34. These three isozymes had almost the same Km's and relative values of Vm's for several substrates, suggesting that they had the same common active site.PII-D and PII-T are more strongly embedded in the membrane than PII-M, because the proportion of PII-D and PII-T was much increased when the remaining glucosidase in the precipitate after the first solubilization was reextracted by DOC. A large peak of α-glucosidase isozyme P-IV which preferentially hydrolyze sucrose eluted just after P-II (soluble P-II) when the supernatant fraction of the labellar homogenate was chromatographed on DEAE-Sephadex A-50. P-IV was scarcely present in the precipitate fraction.Soluble P-II had the same mol. wt as PII-M and had similar properties to PII-M except for the ratio of Vm's.A large proportion of PII-D was contained in the well washed labellar integuments, a preparation rich in labellar chemosensilla. It suggests that most of the insoluble α-glucosidase contained in the dendrite in labellar chemosensilla is PII-D. PII-D (and PII-T) are possible sites of the pyranose receptor molecule because their properties and localization agree well with those of the receptor. 相似文献
33.
Michio Takido Susumu Kitanaka Shushichi Takahashi Tomohisa Tanaka 《Phytochemistry》1982,21(2):425-427
Two new yellow pigments, germitosone and methylgermitorosone, were isolated from the seedling of Cassia torosa. The structures of these substances were established as 3,7 dimethyl - 6 - methoxy - 1 - oxo - 2,3,8,9 - tetrahydroxy - 1,2,3,4 - tetrahydroanthracene and 6,9 dimethoxy - 3,7 - dimethyl - 1 - oxo - 2,3,8 - trihydroxy - 1,2,3,4 - tetrahydroanthracene respectively. 相似文献
34.
Hiroshi Tohoyama Michio Hagiya Kazuo Yoshida Naohike Yanagishina 《Molecular & general genetics : MGG》1979,174(3):269-280
Summary Isolated zygotes showed self-agglutination caused by the sex-specific glycoproteins, the agglutination substances responsible for sexual agglutination. The agglutination substances of both a and mating types were detected in the extracts obtained by the autoclave method from zygotes. Although the first diploid daughter cells from zygotes showed self-agglutinability, the self-agglutinability decreased gradually in the successive diploid daughter cells. The self-agglutination in diploid cells was also brought about by the complementary binding of the sex-specific agglutination substances of opposite mating types.The constitutive sexual agglutinability in a and cells was lost with concomitant loss of the agglutination substances in both cell wall and cytoplasmic fractions when cultured at a temperature higher than 35°C.The repression of the production of the agglutination substances was reversed by the opposite mating type pheromones even at the repressive temperature, 36°C, associated with the appearance of sexual agglutinability. The sex pheromones, a substance-I and substance-I, and the binding substance for substance-I were produced even at 36°C, repressive for the production of the agglutination substances. 相似文献
35.
Quantitative study of the cytochrome c acting in the photosyntheticsystem of the blue-green alga Anabaena variabilis (M-2) wasdone with membrane fragments and intact cells. Membrane fragments highly active in the NADP+-Hill reaction(above 200 µmoles/mg chl.a;-hr) retained photoresponsivecytochrome c equal only one-tenth that of P700, while the plastocyanincontent was almost equal to that of P700. The cytochrome contentin intact cells was a little larger than that in membrane fragmentson the chlorophyll a basis. However, the values relative toP700 (1/9) and plastocyanin (1/10) were identical with thosein membrane fragments. The content was also far smaller thanthat of reaction center II's (1/6). If the cytochrome mediatesall electrons from reaction center II, the cytochrome oxidation-reductionshould have a rate constant of 2.4?102 sec1 which isone order above of the rate constant of the cytochrome reduction(2.3 to 3.5?101sec1). These quantitative relationshipsindicate that in Anabaena variabilis (M-2), c-type cytochrome,either cytochrome f or algal cytochrome c, cannot function inthe main electron flow between two reaction centers. (Received September 8, 1978; ) 相似文献
36.
Thin-layer chromatography (TLC) of ethyl ether-ethanol extracts of mycobacteria obtained after incubation with [35S] methionine is useful for differentiation among mycobacterial species, as the distribution of radioactive spots in TLC shows a characteristic pattern except for a few species, including M. intracellulare and M. gordonae. Some supplementary studies have been carried out in the present investigation and the following results have been obtained.
- 相似文献
37.
The effect of 6059-S, a novel 1-oxacephem, on peptidoglycan synthesis was investigated using ether-treated cells of Escherichia coli K 12, Pseudomonas aeruginosa KM 338 and Serratia marcescens IFO 12648. The cross-linking reaction of peptidoglycan synthesis in these organisms was inhibited by markedly low concentration of 6059-S.Non-standard abbreviations PBP
penicillin binding protein
- MIC
minimum inhibitory concentration
- ETB
ether treated bacterial cells
- SDS
sodium dodecylsulfate 相似文献
38.
Shuhichi Takahashi Susumu Kitanaka Michio Takido Ushino Sankawa Shoji Shibata 《Phytochemistry》1977,16(7):999-1002
From seedlings of Cassia torosa four dimeric hydroanthracenes have been isolated. Two, a pair of atropisomeric dimers consisting of two molecules o 相似文献
39.
Two patterns were found in the shifts of absorption peaks inspectra of intact etiolated Pharbitis cotyledons illuminatedat room temperature. One was a well-known pattern, P649C678C683C672,called the "high-intensity illumination pattern" in this study.The other, called the "low-intensity illumination pattern,"was P649C672. (Received June 16, 1976; ) 相似文献
40.
Lipid peroxide (LPO) formation was remarkable when isolatedtobacco chloroplasts were bubbled with high concentrations ofozone, though the fatty acid composition and the fractionationpattern of glycolipids and phospholipids in the chloroplastlipids changed little after ozone fumigation of the leaves.Piperonyl butoxide (PB), a potent protectant against ozone injury,strongly inhibited LPO formation in ozonated chloroplasts. PBalso prevented ozone-induced decreases in the amounts of linolenicand linoleic acids in the chloroplast lipids. These resultssuggest that PB inhibition of LPO formation may be involvedin the protective mechanism against ozone phytotoxicity. However,the mode of PB action differed on some points from that of diphenylamine,which is an antioxidant and also effective against ozone injury.The mode of PB action is discussed.
1 Present address: The Central Research Institute, Japan Tobacco& Salt Public Corporation, Umegaoka, Midori-ku, Yokohama227, Japan. (Received July 5, 1976; ) 相似文献