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1.
2.
Using Toyopearl and cyclohexane: cyclohexanol solvent, fourCl-containing Chls were separated from 36Cl-labeled cells ofthe blue-green, Plectonema boryanum. In normally grown cells,all four Cl-containing chlorophylls amounted to less than 1/2,000of the total Chi and about 1/50 of P700, values much lower thanpreviously reportedcontents of Chi RC I, and varied from algato alga. The level of Cl-containing Chi was markedly enhancedwhen the cells were poisoned with methyl viologen. These resultssuggests that these Cl-containing Chls are not related to thereaction center of PS I. (Received June 23, 1987; Accepted September 17, 1987) 相似文献
3.
The usual Bligh and Dyer method could extract only a small part of the lipids of Methanobacterium thermoautotrophicum. When the water in the solvent was replaced by 5% trichloroacetic acid, the lipid recovery reached the maximum level, which was 6 times higher than that by the former method. The use of HCl (2 M) or disruption of cells was also effective but prolonged extraction with the HCl-containing solvent caused degradation of some phosphoglycolipids. Twenty-three spots of polar lipids were detected on a thin-layer chromatogram of the total lipid. These were 10 phospholipids (18%), 6 aminophospholipids (17%), 3 aminophosphoglycolipids (15%), 2 phosphoglycolipids (31%), and 2 glycolipids (19%). The predominant polar lipids were a highly polar phosphoglycolipid (PGL1, 30%) and a glycolipid (GL1a, 16%). The other major lipids included an aminophospholipid (PNL1a, 9%), and an aminophosphoglycolipid (PNGL1, 7%). The complete structure determination of PNL1a, GL1a, and PNGL1 is described in the accompanying paper. Acetolysis of the total lipids followed by acid methanolysis was required for the complete cleavage of polar head groups, releasing core residues of diphytanyl glycerol diether (C20 diether) and dibiphytanyl diglycerol tetraether (C40 tetraether). A densitometric assay of a thin-layer chromatogram showed that the ratio of C20 diether and C40 tetraether was 1:14. GLC analysis of alkyl chlorides prepared from the total lipid by BCl3 treatment showed that phytanyl (C20), biphytanyl (C40), and unidentified alkyl chains accounted for 10, 83, and 7 mol% of the total alkyl chains, respectively. Strong acid hydrolysis of the macromolecular residue obtained after lipid extraction gave a significant amount of C40 tetraether, which had probably been bound covalently to other substances in the cells. 相似文献
4.
Immigration of the brown planthopper, Nilaparvata lugens, exhibiting various responses to density in relation to wing morphism 总被引:6,自引:0,他引:6
Considerable inherent variations in the relation between macropterous and brachypterous wing forms, and nymphal density were found in field populations of the brown planthopper, Nilaparvata lugens Stål (Homoptera: Delphacidae), collected from various locations in Japan. When compared under uniform laboratory rearing conditions, most of the female populations exhibited higher ratios of macropters with increasing nymphal density, but some showed extremely high proportion of brachypters and the others were highly macropterous, over broad ranges of density. These results indicate the possibility that the planthoppers in Japan, which are known not to persist in winter, are derived from different migration sources.About ten generations of successive selection for brachyptery from a population showing usual density-dependent wing morphism generated populations similar to highly brachypterous ones mentioned above. Genetic analysis of the inheritance of wing morphism revealed that brachyptery in the females was controlled by a single pair of dominant alleles. However, in the males wing forms did not segregate so clearly in the crossing experiments. This suggests that wing morphism in N. lugens in under sex-limited inheritance.
Einwanderung von Nilaparvata lugens mit unterscheidlicher Reaktion auf Populationsdischte bei der Flügelausbildung
Zusammenfassung In Feldpopulationen von Nilaparvata lugens Stål., welche in verschiedenen Regionen Japans gesammelt wurden, bestand in der Beziehung zwischen makropteren bzw. brachypteren Flügelformen und der Larvendichte eine beträchtliche Variation. Unter einheitlichen Zuchtbedingungen im Laboratorium stieg der Makropterenanteil bei den meisten Weibchenpopulationen mit steigender Temperatur; bei einigen Populationen hingegen war entweder der Brachypterenanteil oder der Makropterenanteil extrem hoch und zwar über weite Dichtebereiche. Dies deutet auf die Möglichkeit hin, dass die Zikade in Japan, wo sie bekanntlich nicht überwintert, jeweils aus verschiedenen Quellen einwandert.Wenn eine Population mit der üblichen dichteabhängigen Flügelausbildung 10 Generationen lang auf Brachypterie selektioniert wurde, entstanden Populationen, die den erwähnten hochbrachypteren Populationen aus dem Feld glichen. Die genetische Analyse der Vererbung der Brachypterie ergab, dass bei Weibchen ein einzelnes dominantes Allel verantwortlich ist. Bei Männchen dagegen trennten sich bei Kreuzungsexperimenten die Flügelformen nicht so klar. Dies deuted auf Unterschiede zwischen den Geschlechtern bei der Vererbung der Flügelformen.相似文献
5.
Level of translatable messenger RNA coding for argininosuccinate synthetase in the liver of the patients with quantitative-type citrullinemia 总被引:2,自引:0,他引:2
Mariko Sase Keiko Kobayashi Yasushi Imamura Takeyori Saheki Kyoko Nakano Satoshi Miura Masataka Mori 《Human genetics》1985,69(2):130-134
Summary The translation activity of mRNA coding for argininosuccinate synthetase in total RNA extracted from the liver of three patients with quantitative-type citrullinemia was determined using a cell-free translation system. In two patients, the hepatic content of the enzyme was about 20% of the control value, whereas translatable mRNA level for the enzyme was similar to or slightly lower than those of control livers. In the third patient, the enzyme content was about 50% of the control value, and mRNA activity for the enzyme was low normal. These results indicate that at least in the first two patients, the decrease in the enzyme protein is due either to increased degradation of the enzyme or to decreased translation in the patient's liver. 相似文献
6.
The effect of gamma-aminobutyric acid (GABA) on antidromically identified tubero-infundibular (TI) neurons was examined in hypothalamic slices of ovariectomized female rats. Twenty antidromically evoked spikes were obtained in the medial basal hypothalamus, including the arcuate and ventromedial nuclei, by electrical stimulation of the median eminence. Sixteen of them had a notch in the rising phase and fractionation of the initial segment (IS)- and somatodendritic (SD)-spikes was elicited by repeated stimulation at frequencies higher than 10 Hz. The application of 0.5-1.5 mM GABA to the incubation medium inhibited SD spikes in 7 of these 16 neurons. The latency, amplitude and threshold of IS spikes were not affected by GABA except for one spike whose latency fluctuated. On the remaining 9 neurons having the notch, no effect of 5-10 mM GABA was discernible. Four of 20 antidromically evoked spikes, which had a smooth rising phase and a shorter duration, were not inhibited by 5-10 mM GABA, but a fluctuation of the latency was observed in one neuron. Fifteen neurons having spontaneous unit activity were also obtained in the arcuate nucleus and its adjacent area and tested with GABA. In 10 of the 15 neurons, spontaneous unit activity disappeared following 0.1-1.5 mM GABA perfusion, while the firing rate in the remaining 5 neurons was not affected by 5-10 mM GABA. These results provide evidence for a direct inhibitory effect of GABA on TI neurons and support the involvement of GABAergic neurons in regulating neuroendocrine functions. 相似文献
7.
Biological Activity of 5-Hydroxymethyluracil and Its Deoxynucleoside in Noninfected and Phageinfected Bacillus subtilis 总被引:4,自引:3,他引:1
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(14)C-hydroxymethyldeoxyuridine (dHMU) is specifically incorporated into the deoxyribonucleic acid (DNA) of bacteriophage SP8. Incorporation experiments demonstrate that the initiation of phage SP8 DNA synthesis occurs between 12.5 to 15 min after infection. Incorporation into host DNA does not occur. (14)C-dHMU can be used as an analytical tool for screening conditionally lethal phage mutants containing hydroxymethyluracil in their DNA to select those that are defective in DNA synthesis under restrictive conditions. The pyrimidine, (14)C-hydroxymethyluracil (HMU), is not incorporated into bacterial or phage DNA. Neither HMU nor dHMU can replace thymine as a growth requirement for Bacillus subtilis 168 Ind(-) Thy(-). HMU does not inhibit the utilization of thymine. Although dHMU inhibits deoxythymidine utilization, the inhibition is not competitive. 相似文献
8.
Effect of Ca on composition of fat body of peanut seed 总被引:1,自引:0,他引:1
Peanut fruits were grown in nutrient media with or without Ca and in a soil with two Ca levels, from the 20th day after penetration
of the gynophore. Seed weight was smaller in the nutrient medium without Ca than in the nutrient medium with Ca, and it was
also smaller in the soil with 4 meq of exchangeable Ca (L treatment) than in the soil with 10 meq of exchangeable Ca (H treatment).
The fat body of seeds from the Ca deficient medium and the L treatment had a decreased phospholipid content and an increased
simple lipid content. In the seed from the H treatment, phosphatidylcholine increased from the 30th to 60th day, while caldiolipin
decreased. The amount of triglyceride in the simple lipid content of fat body was decreased by Ca deficiency in the nutrient
medium, whereas that of diglyceride was increased, but these effects were not observed in the fat body of the seed from the
L treatment. No effect of Ca deficiency was observed in the fatty acid composition of triglyceride. 相似文献
9.
Haruko Ogawa Ako Hijikata Maho Amano Kyoko Kojima Hisako Fukushima Ineo Ishizuka Yoshie Kurihara Isamu Matsumoto 《Glycoconjugate journal》1996,13(4):555-566
The oligosaccharide structures ofCry j I, a major allergenic glycoprotein ofCryptomeria japonica (Japanese cedar, sugi), were analysed by 400 MHz1H-NMR and two-dimensional sugar mapping analyses. The four major fractions comprised a series of biantennary complex type N-linked oligosaccharides that share a fucose/xylose-containing core and glucosamine branches including a novel structure with a nongalactosylated fucosylglucosamine branch.Rabbit polyclonal anti-Cry j I IgG antibodies cross-reacted with three different plant glycoproteins having the same or shorter N-linked oligosaccharides asCry j I. ELISA and ELISA inhibition studies with intact glycoproteins, glycopeptides and peptides indicated that both anti-Cry j I IgGs and anti-Sophora japonica bark lectin II (B-SJA-II) IgGs included oligosaccharide-specific antibodies with different specificities, and that the epitopic structures against anti-Cry j I IgGs include a branch containing 1–6 linked fucose and a core containing fucose/xylose, while those against anti-B-SJA-II IgGs include nonreducing terminal mannose residues. The cross-reactivities of human allergic sera to miraculin andClerodendron Trichotomum lectin (CTA) were low, and inhibition studies suggested that the oligosaccharides onCry j I contribute little or only conformationally to the reactivity of specific IgE antibodies.Abbreviations
Cry j I
a major allergenic glycoprotein ofCryptomeria japonica
- B-SJA-II
Sophora japonica bark lectin II
- CTA
Clerodendron trichotomum lectin
- TFMS
trifluoromethanesulfonic acid
- HRP
horseradish peroxidase 相似文献
10.
Kunio Takeda Kyoko Ogawa Masami Ohara Satoshi Hamada Yoshiko Moriyama 《The protein journal》1995,14(8):679-684
Four disulfide bridges of bovineα-lactalbumin (α-lact) were selectively reduced to obtain its derivatives with three, two, and zero disulfide bridges (designated as 3SS, 2SS, and OSSα-lact, respectively). The original helicity was almost maintained in 3SSα-lact missing only the Cys6-Cysl20 bridge. Upon the reduction of both Cys28-Cys111 and Cys6-Cys120 bridges, various changes occurred in the protein. In particular, the maximum fluorescence of 1-anilinonaphthalene-8-sulfonic acid was observed in this stage. Upon the reduction of all disulfide bridges, the hydrophobic box of the protein, formed by Trp60, Ile95, Tyr103, and Trp104, was disrupted and an internal helical structure was destroyed. The conformation of each derivative was examined mainly in a solution of sodium dodecyl sulfate. In the surfactant solution, the helicity increased from 33% to 37% in 3SSα-lact, from 26% to 31% in 2SSα-lact, and from 18% to 37% in OSSα-lact, as against from 34% to 44% in intactα-lact. On the other hand, the tryptophan fluorescence of each derivative was affected in very low surfactant concentrations, suggesting that the tertiary structure considerably changed prior to the secondary structural change in the surfactant solution. 相似文献