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We previously isolated and characterized a new free amino acid withd-configuration at the α-carbon,trans-3, 4-dehydro-d-2-aminopimelic acid and its related amino acids,d-2-aminopimelic acid and 4-hydroxy-l-2-aminopimelic acid fromAsplenium unilaterale. In this paper, we report that the biosynthetic relationshps among these three amino acids were studied using14C-and3H-labeled compounds as tracers. Glutamate and aspartate were shown to be good precursors and it was suggested that 4-hydroxy-l-2-aminopimelic acid is biosynthesized first and the twod-amino acids are derived from it. Furthermore, the distribution patterns of these non-protein amino acids inAsplenium sect.Hymenasplenium were examined in detail and they were evaluated by their biosynthetic pathway. Morphological characters especially on their
rhizomes were also examined and their character phylogeny was determined by outgroup comparison. Taking all the characters
available into account, the phylogenetic relationship among 7 species ofAsplenium sect.Hymenasplenium in Japan and Taiwan is discussed by the transformed cladistic method. 相似文献
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The phloroglucinol composition of species and synthesised hybrids of the Dryopteris carthusiana complex has been examined. Hybrids appear to show the influence of either, or both, of the parental species. The significance of these results to the evolution of species within the complex is discussed. 相似文献
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Twelve amino acids were detected in six davaineid cestodes, Davainea hewetensis Dhawan & Capoor (1972) collected from one Gallus gallus domesticus L. at Allahabad, India. Chemotaxonomic studies within the family Davaineidae have shown the presence of cystine and hydroxyproline only in D. hewetensis, although phenylalanine and proline occur in all species examined previously. 相似文献
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Phenetic variation found in JapaneseArachniodes was compared with phloroglucinol composition. The differences in this chemotaxonomic feature were not found very useful in
defining the taxa inArachniodes. The phloroglucinol compositions of the putative hybrids were determined and compared with those of the presumed parent species.
It was concluded that, in general, the hybrids combine the phloroglucinols found in their parent species. Hybridization among
the Japanese species ofArachniodes should, however, be confirmed by cytological investigations.
Five species of Kalimantan (Bornean) ferns were also studied for their phloroglucinol contents.Arachniodes tripinnata was compared with Philippine materials of the same species with the result that they differed to some extent. In addition,
four species belonging to Tectarioideae were examined:Heterogonium is devoid of phloroglucinols, andPleocnemia irregularis contains a great deal of a “yellow compound” of unknown structure. 相似文献
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Carl-Johan Widén Antero Huure Jaakko Sarvela Kunio Iwatsuki 《Journal of plant research》1978,91(4):247-254
Seven species ofArachniodes from Japan and the Philippines were examined for phloroglucinol derivatives and glandularity of rhizome and petiole bases.
For comparison 3 species ofDryopteris, 2 species ofNothoperanema, 3 species ofPolystichum, 1 species ofAcrophorus and 2 species ofCtenitis were investigated as well.
Phloroglucinol derivatives were detected for the first time in the following taxa:Arachniodes assamica, A. cavalerii, A. tripinnata, A. yasu-inouei, Dryopteris pulvinulifera, D. cochleata, Polystichum rigens,
Acrophorus nodosus, Ctenitis setosa andC. subglandulosa. The phloroglucinols ofDryopteris, Arachniodes andPolystichum are structurally related in agreement with the taxonomic relationships of these genera. On the other hand, the less related
generaAcrophorus andCtenitis contain several unknown phloroglucinols not identical with those occurring in the former genera. The phloroglucinol containing
species ofArachniodes, Polystichum, Acrophorus andCtenitis contain external glands, whereasDryopteris pulvinulifera andD. cochleata have both internal and external glands.
The species of the genusNothoperanema seem to completely lack phloroglucinols and glands.
The phloroglucinol composition of most taxa investigated is almost constant except for that inArachnoides amabilis and its varieties,A. aristata (A. exilis) andPolystichum tsus-simense. These species show varying phloroglucinol spectra in materials collected from different geographical sources. 相似文献
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The optical activity of the Klebsiella capsular polysaccharides of serotypes K1, K5, K6, K8, K11, K56, and K57 has been studied in aqueous solution. Measurements of ORD in the range 185–450 nm reveal anomalous ORD with Cotton effects near λ0 = 195nm. The results are evaluated quantitatively according to hte Moffitt-Yang and the Drude equations. Straight lines are obtained in the Moffitt-Yang plots, while the corresponding Drude plots yield bent curves. The b0 values, calculated from the slope of the stright lines in the Moffitt-Yang plot, range from 90 to 270 and suggest a helical superstructure for the capsular polysaccyharides. Positive b0 values have been found for K1, K5, and K6 and negative b0 values for K8, k11, K56, ad K57. Circular dichrosim has been mesured, but the CD curves are found to be truncated at the lower-wavelength end due to the 185-nm limit of the spectrometer used. Measurements of the temperature dependence of the specific optical rotation [α] reveal in all cases cooperative order–disorder transitions at temperatures, Tm, fro m298 to 323°K. The van′t Hoff enthalpies derived from the width of the transition curves are found to be similar in value to those of polypeptieds in aqueous solution. The K8 polysaccharide shows a two-step transition. The results are discussed in relation to the known primary structure and x-ray data from oriented and partially crystalline films. A model is suggested for the two-step transition in the K8 polysaccharide. 相似文献
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Chemical and immunological studies on mycobacterial polysaccharides. 1. Purification and properties of polysaccharides from human tubercle bacilli 总被引:7,自引:4,他引:7
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Defatted human tubercle bacilli, Aoyama B strain, were extracted with 0.1 n NaOH for 24 hr, and the crude polysaccharide fraction was precipitated by the addition of 5 volumes of ethyl alcohol. A yield of 17.8 g of crude polysaccharides was obtained from 800 g of bacilli. The crude polysaccharide was further fractionated into seven fractions by fractional precipitation with ethyl alcohol. Each fraction was purified by successive chromatography on Dowex 50 and diethylaminoethyl cellulose, and by gel filtration on Sephadex G-75 and G-200. Optical rotation and gas chromatographic analyses of purified polysaccharide showed that these polysaccharides contained glucan mannan, arabinomannan, and arabinogalactan. Each polysaccharide was almost completely free from nitrogen, and no tuberculin reaction was produced by 100 mug of each material. Arabinomannan and arabinogalactan showed precipitin reaction, complement fixation, and passive hemagglutination reaction with rabbit antiserum against heat-killed whole bacilli (Aoyama B). In guinea pigs sensitized with Aoyama B bacilli, arabinomannan and arabinogalactan provoked anaphylactic shock when injected intravenously, and Arthus type reaction when injected intracutaneously. With the use of rabbit antiserum, arabinomannan and arabinogalactan showed passive anaphylactic shock, passive cutaneous anaphylaxis, and Prausnitz-Küstner type reactions in guinea pigs. By immunodiffusion analysis, it was shown that the antigenic determinant of arabinomannan was different from that of arabinogalactan. 相似文献
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木通科植物的化学分类 总被引:13,自引:0,他引:13
木能科为双子叶植物纲中较原始的一个小科,多为寡种属和单种属,主要分布于东亚地区。我国共有7属29种,其中很多种为传统的药用植物。本文简要综述木通科植物近几十年的化学研究状况,并从化学分类学 的角度探讨木通科属间和与其近缘科之间的系统关系。结果表明齐墩果烷型三匝皂甙作为木通科的特征化不成发在该科的系统分类中具有一定的意义。齐墩果烷型三萜皂甙不仅提示木通科与毛莨科的毛莨亚科的系统联系,而且甙元骨架的氧化水平与科内各属的系统进货也有一定的相关性。 相似文献
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X-ray diffraction studies on the connective tissue polysaccharides. Molecular conformations of dermatan sulphate 总被引:2,自引:0,他引:2
Three distinct molecular conformations of the connective tissue polysaccharide dermatan sulphate have been observed by X-ray diffraction. These comprise an 8-fold type helix, a 3-fold helix and a 2-fold helix with disaccharide repeats projected onto the helix axis of 0.93 nm, 0.96 nm and 0.97 nm, respectively. The relative merits of the various 8-fold helices are discussed. The evidence favours the l-iduronic acid moiety to be in the Cl chair form for all three structures. 相似文献
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A variety of nmr transient techniques demonstrate the absence of domain structures in powders of α- and β-cyclodextrins, dextran B512F, and their “deuterated” analogs where deuterium replaces exchangeable protons. Cyclodextrins and dextran are inferred to be homogeneously ordered and disordered one-phase systems, respectively. We show how erroneous results concerning the presence and sizes of rigid and mobile domains can be reached from the interpretations of two-component free induction decays and spin–lattice relaxation behavior of polysaccharides. In our approach, we have measured 1H free induction decays and lineshapes, and 1H spin–lattice and dipolar relaxation times, in addition to using Goldman–Shen experiments and 13C cross-polarization magic-angel sample spinning. Self-consistent nmr results are suggested as essential means to corroborate conclusions concerning domain structures in biopolymers. 相似文献
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M. JAY 《Botanical journal of the Linnean Society. Linnean Society of London》1969,62(4):423-429
Very homogeneous chemically, the genus Pittosporutn is characterized by the absence of leucoanthocyanidins, ellagic acid and phenyl-trihydroxylated compounds. This chemical definition seems to be applicable to the whole family.
Although a relationship between Pittosporum and the Saxifragaceae is not to be rejected categorically, it seems preferable, considering the polyphenols data and some anatomical features, to place Pittosporum near the Umbelliflorae rather than near the Saxifragaceae. 相似文献
Although a relationship between Pittosporum and the Saxifragaceae is not to be rejected categorically, it seems preferable, considering the polyphenols data and some anatomical features, to place Pittosporum near the Umbelliflorae rather than near the Saxifragaceae. 相似文献
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Jürgen Jacob 《Biochemical Systematics and Ecology》1979,7(2):141-145
The cuticular lipids of nine species of beetles (Coleoptera) belonging to different superfamilies were analysed and found to consist of aliphatic hydrocarbons: n-alkanes, 2-, 3-, and other monomethylalkanes as well as dimethylalkanes and alkenes. The hydrocarbon pattern is qualitatively constant at the family level but varies from family to family and thus may be of use in the taxonomy of the insects. 相似文献
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The uropygial gland secretions of Charadriiformes species (Thinocorus rumicivorus, Gallinago gallinago, Scolopax rusticola) were analysed and the quantitative compositions compared with those of other Charadriiformes and Lariformes species. The results are discussed from a chemotaxonomic viewpoint and evidence for a close relationship between Thinocorus and other Charadriiformes is given. 相似文献
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R. NOURISH R. W. A. OLIVER 《Biological journal of the Linnean Society. Linnean Society of London》1974,6(3):259-268
Twenty-one specimens appear under the name 'Lichen rangiferinus' in the Linnaean Herbarium. Small fragments of these specimens have been subjected to chemical analysis for the first time using one or more of the following techniques: Lichen mass spectrometry, Ultraviolet spectrophotometry and Thin layer chromatography. The results, which have been stored in full on computer tape, are summarized and discussed in relation to the morphology and annotation of the lichens concerned. These studies have led to the selection of the specimen on sheet number 1273.240 as the lectotype of Lichen rangiferinus L. The fact that the chemical analysis of this specimen was carried out on less than 0.5 milligrams of thallus indicates the power of contemporary physicochemical methods in Herbarium studies of this nature. 相似文献