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1.
The sieve-element plastids of 69 species of theCaryophyllales were investigated by transmission electron microscopy. All contained the specific subtype-P3 plastids characterized by a peripheral ring of protein filaments. The presence or absence of an additional central protein crystal and their shape being either polygonal or globular as well as the average sizes of the sieve-element plastids are useful features in the characterization of some families.—Barbeuia contains sieve-element plastids that confirm its placement within thePhytolaccaceae. Lyallia differs fromHectorella by including small starch grains in their sieve-element plastids, which otherwise by their globular crystals negate a closer connection to theCaryophyllaceae. The lack of a central protein crystal in its form-P3fs plastids placesMicrotea best within theChenopodiaceae. Sarcobatus, a so far uncontested member of theChenopodiaceae, contains form-P3cf plastids, i.e., including a central crystal not found elsewhere in this family.Telephium andCorrigiola, shifted back and forth betweenMolluginaceae andCaryophyllaceae, have form-P3cf(s) plastids with a polygonal crystal which favor their placement within theCaryophyllaceae.  相似文献   

2.
The tribal name Bocageeae Endlicher is reestablished and the tribe is circumscribed on the basis of solitary internodal ebracteate pedicels that are articulated at the base, and pollen shed in polyads of eight or more grains. Septate anther locules, large pollen size, and seed appendages are prevalent in the tribe. Intectate pollen with free-standing columellae, rare in Annonaceae, occurs not only in the genusTrigynaea but also in some species ofBocagea andHornschuchia. As defined here, the Bocageeae include seven neotropical genera:Cymbopetalum, Porcelia, Bocagea, Cardiopetalum, Froesiodendron, Hornschuchia, andTrigynaea. The latter five genera are revised and the treatments include ten new species:Cardiopetalum plicatum, Froesiodendron urceocalyx, Hornschuchia lianarum, H. santosii, H. leptandra, Trigynaea cinnamomea, T. lanceipetala, T. triplinervis, T. lagaropoda, andT. axilliflora, all from tropical South America. A new combination,Froesiodendron longicuspe, changes the rank of that taxon from subspecies to species.Cardiopetalum surinamense is removed fromFroesiodendron and reassigned toCardiopetalum on the basis of its connate petals, dehiscent monocarps, and seeds with bilobed arils. A cladogram provides an explicit hypothesis of intergeneric relationships in the tribe. The new combinationOnychopetalum periquino, based onTrigynaea periquino, is made.  相似文献   

3.
The two generaPlectranthus andIsodon are compared and found to be very dissimilar.Isodon ist considered to be misplaced inOcimeae subtribePlectranthinae and apparently is more closely related to subtribeHyptidinae. The disjunct genusRabdosiella is compared to these two genera and regarded to be polyphyletic. The AfricanR. calycina (Benth.)Codd is returned toPlectranthus and calledP. calycinus Benth., while the AsianR. ternifolia (D. Don)Codd is placed inIsodon sect.Pyramidium and calledI. ternifolius (D. Don)Kudo.  相似文献   

4.
Type strains of bacteria of the genera Alteromonas, Pseudoalteromonas, Marinomonas, and Marinobacterand symbiotrophic bacteria isolated from the Far Eastern bivalve mollusks Crenomytilus grayanusand Mizuhopecten yessoensisand identified as Pseudoalteromonas nigrifaciensand P. citreawere tested for susceptibility to antibiotics. Of the ten antibiotics used in this study, benzylpenicillin, polymyxin, lincomycin, and oleandomycin were valuable for the polyphasic taxonomy of marine aerobic proteobacteria. Marine bacteria of the genera studied exhibited characteristic antibiotic susceptibility profiles, which were useful for the differentiation of the genera.  相似文献   

5.
6.
Pratt RG 《Mycopathologia》2006,162(2):133-140
Nine species of Bipolaris, Curvularia, Drechslera, and Exserohilum were compared for sporulation on agar media and for enhancement of sporulation by growth on four cellulose-containing substrates (index card, filter paper, cheesecloth, cotton fabric). On two natural and one synthetic agar media, sporulation varied from profuse to nonexistent among three isolates of each species. Growth of all species on cellulose substrates resulted in large and significant increases in sporulation. Growth on index card pieces often provided the greatest increases, but no single substrate was superior for all species, and significant substrate × isolate interactions were observed within species. Overlay of filter paper onto whole colonies in agar plates resulted in 2 to 18-fold increases in sporulation for eight of nine species and production of spores in sufficient quantity for most experimental purposes. Overlay of soil dilution plates with filter paper to promote sporulation of colonies enabled detection of B. spicifera, B. hawaiiensis, C. lunata, and E. rostratum at relatively low population levels (≤1.3 × 103 colony-forming units per gram of soil) in samples of a naturally infested soil. Results indicate that enhancement of sporulation by growth of species of Bipolaris, Curvularia, Drechslera, and Exserohilum on cellulose substrates may facilitate (i) their identification in culture, (ii) production of spores at relatively high concentrations, and (iii) detection and enumeration of these fungi in soil.  相似文献   

7.
Cytochromes b, c, d, and o were identified by spectroscopic analysis of respiratory membrane fragments from Vitreoscilla sp., strain C1. Carbon monoxide difference spectra of the reduced membranes had absorption maxima at 416, 534, and 571 nm (ascribed to cytochrome o) and 632 nm (cytochrome d). Derivative spectra of the pyridine hemochromogen spectra of the membranes identified the presence of b- and c-type cytochromes in Vitreoscilla. The cyanide binding curve of the membranes was biphasic with dissociation constants of 2.14 mM and 10.7 mM which were assigned to cytochrome o and cytochrome d, respectively. Membranes bound carbon monoxide with dissociation constant 3.9 M, which was assigned to cytochrome o. Cytochrome c 556 and a NADH-p-iodonitrotetrazolium violet reductase component were partially purified from Vitreoscilla membranes.Abbreviations INT p-iodonitrotetrazolium violet - RMF respiratory membrane fragments - K d dissociation constant - CHAPS 3-[(3-cholamido propyl) dimethylammonio]-1-propanesulfonate - DOC sodium deoxycholate - PAGE polyacrylamide gel electrophoresis - SDS sodium dodecyl sulfate  相似文献   

8.
We examined the patterns of distribution, vectors of introduction, and potential ecological impacts of freshwater exotic species in Texas over the last 45 years. Currently, five species of exotic gastropods are established: channeled-type applesnail (Pomacea insularum), red-rim melania (Melanoides tuberculatus), quilted melania (Tarebia granifera), giant rams-horn snail (Marisa cornuarietis), and Chinese mysterysnail (Cipangopaludina chinensis). In contrast to the northern part of the US, where shipping appears to be the most important vector for the introduction of aquatic invasive species, aquarium and ornamental trade dominated among unintentional vectors of introduction of all freshwater exotics in Texas, resulting in different patterns of distribution, spread, and ecological impacts. The rate of spread of exotic gastropods in Texas varied from 39 waterbodies colonized over 18 years for P. insularum to only three waterbodies during last 45 years for C. chinensis. Four of five exotic gastropods were found in highly vulnerable aquifer-fed springs and rivers, which contain numerous endemic and endangered species. The fifth species, Pomacea insularum, is an agricultural pest. Potential negative ecological effects of exotic gastropods include impacts on wetlands and wetland restoration, competitive exclusion of native snails, and the introduction of exotic parasites, trematodes, which could infect fish and waterfowl, including federally protected species. Aquifer springs with stable temperature regimes are refuges for both cold and warm intolerant species. Handling editor: D. Dudgeon  相似文献   

9.
Spirulina platensis and Spirulina maxima were characterized by 16S ribosomal RNA oligonucleotide cataloguing. Both species are highly related. They fall into the main group of the cyanobacteria, showing a remote relationship to Nostoc, Fischerella, Aphanocapsa, and also to Prochloron. Low similarity coefficients were found between the Spirulina species and certain organotrophic and sulfide oxidizing bacteria, viz. Saprospira grandis, Vitreoscilla stercoraria, Leucothrix mucor, Herpetosiphon aurantiacus, and Beggiatoa leptomitiformis, respectively. This result does not support the classical hypothesis that certain filamentous gliding bacteria are apochlorotic cyanobacteria.  相似文献   

10.
The new genusCaucasalia is described. Four species are included, previously referred toSenecio, Cacalia, Cineraria, Pojarkovia orAdenostyles. The latter genus may be the closest relative, being similar in habit and chromosome number, but different in floret colour and style morphology. The new genus is centered in the Caucasus mountains, with extensions into Anatolia.Dedicated to emer. Univ.-Prof. DrFriedrich Ehrendorfer on the occasion of his 70th birthday  相似文献   

11.
A peptide antibiotic with cyanolytic activity was isolated from the IGM52 strain of the Brevibacillus laterosporus Gram-positive spore-forming bacteria. By 1H NMR spectroscopy, this antibiotic was identified as loloatin A, a cyclic decapeptide cyclo(-Asn-Asp-Tyr-Val-Orn-Leu-D-Tyr-Pro-Phe-D-Phe-). The spatial structure of loloatin A in solution was determined.  相似文献   

12.
Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.
  相似文献   

13.
Lennon AM  Prommeenate P  Nixon PJ 《Planta》2003,218(2):254-260
The chloroplasts of many plants contain not only the photosynthetic electron transport chain, but also two enzymes, Ndh and IMMUTANS, which might participate in a chloroplast respiratory chain. IMMUTANS encodes a protein with strong similarities to the mitochondrial alternative oxidase and hence is likely to be a plastoquinol oxidase. The Ndh complex is a homologue of complex I of mitochondria and eubacteria and is considered to be a plastoquinone reductase. As yet these components have not been purified to homogeneity and their expression and orientation within the thylakoid remain ill-defined. Here we show that the IMMUTANS protein, like the Ndh complex, is a minor component of the thylakoid membrane and is localised to the stromal lamellae. Protease digestion of intact and broken thylakoids indicates that both Ndh and IMMUTANS are orientated towards the stromal phase of the membrane in Spinacia oleracea L. Such an orientation is consistent with a role for the Ndh complex in the energisation of the plastid membrane. In expression studies we show that IMMUTANS and the Ndh complex are present throughout the development of both Pisum sativum L. cv Progress No. 9 and Arabidopsis thaliana (L.) Heynh. leaves, from early expansion to early senescence. Interestingly, both the Ndh complex and the IMMUTANS protein accumulate within etiolated leaf tissue, lacking the photosystem II complex, consistent with roles outside photosynthetic electron transport.Abbreviations PQ plastoquinone - PSI, PSII photosystem I, II  相似文献   

14.
Ivanova  E. P.  Mikhailov  V. V. 《Microbiology》2001,70(1):10-17
The taxonomic positions of the marine genera Alteromonas, Pseudoalteromonas, Idiomarina, and Colwellia within the gamma subclass of the class Proteobacteria were specified on the basis of their phenotypic, genotypic, and phylogenetic characteristics. Gram-negative aerobic bacteria of the genera Alteromonas, Pseudoalteromonas, and Idiomarina and facultatively anaerobic bacteria of the genus Colwellia were found to form a phylogenetic cluster with a 16S rRNA sequence homology of 90% or higher. The characteristics of these genera presented in this paper allow their reliable taxonomic identification. Based on the analysis of our experimental data and analyses available in the literature, we propose to combine the genera Alteromonas, Pseudoalteromonas, Idiomarina, and Colwellia into a new family, Alteromonadaceae fam. nov., with the type genus Alteromonas.  相似文献   

15.
Xu T  Xin M  Li M  Huang H  Zhou S  Liu J 《Carbohydrate research》2011,346(15):2445-2450
N,N,N-Trimethyl O-(2-hydroxy-3-trimethylammonium propyl) chitosans (TMHTMAPC) with different degrees of O-substitution were synthesized by reacting O-methyl-free N,N,N-trimethyl chitosan (TMC) with 3-chloro-2-hydroxy-propyl trimethyl ammonium chloride (CHPTMAC). The products were characterized by 1H NMR, FTIR and TGA, and investigated for antibacterial activity against Staphylococcus aureus and Escherichia coli under weakly acidic (pH 5.5) and weakly basic (pH 7.2) conditions. TMHTMAPC exhibited enhanced antibacterial activity compared with TMC, and the activity of TMHTMAPC increased with an increase in the degree of substitution. Divalent cations (Ba2+ and Ca2+) strongly reduced the antibacterial activity of chitosan, O-carboxymethyl chitosan and N,N,N-trimethyl-O-carboxymethyl chitosan, but the repression on the antibacterial activity of TMC and TMHTMAPC was weaker. This indicates that the free amino group on chitosan backbone is the main functional group interacting with divalent cations. The existence of 100 mM Na+ slightly reduced the antibacterial activity of both chitosan and its derivatives.  相似文献   

16.
Surface area measurements were performed on the articular facets in the human hand joints in order to calculate the area-asymmetry (incongruency) between mutual articular facets in every one of the hand joints, and to learn about the relations between the asymmetry in the joint, the joint's morphology, and the range of movement exhibited by it. Several different trials have led to the conclusion that the asymmetry in a joint is strongly influenced by its morphological type (plane; sellar; condyloid; bicondylar). No such correlation was found between the asymmetry in a joint and its characteristic range of movement. The results contradict the intuitive assumption that the greater the incongruency in a joint, the wider the movement it can perform.  相似文献   

17.
The sale of non-cultivated plants poses a real threat to the survival of a large number of plant species. On the other hand, the fact that a given plant has become a traded item is an important lead in the effort to investigate plants for the purpose of discovering novel secondary metabolites that may have marketable properties. This report is largely based on the investigations of plants collected from vendors of medicinal plants. The identification is based on botanical specimens derived from the purchased plant parts either by growing them in a garden or through micropropagation using tissue culture techniques. Bulbine species yielded novel phenyl anthraquinones and isofuranonaphthoquinones, which were found to exhibit antiparasitic and antioxidant properties. Scilla nervosa subsp. rigidifolia and Ledebouria graminifolia yielded twenty homoisoflavonoids and two xanthones. Bulbs derived from tissue culture based specimens of L. graminifolia contained all the compounds isolated from the marketed samples. Some of the homoisoflavonoids were found to possess activity against colon and breast cancer cell lines. Rhus pyroides furnished six novel bichalcones some of which exhibited insect antifeedant, cytotoxic and antiproliferative activities. Structures of the compounds described in this report were elucidated by spectroscopic means including HRMS and 1D-, and 2D-NMR experiments. Interconversion of some of the phenyl anthraquinones was accomplished as part of their structure proof. The total synthesis of three of the biflavonoids was achieved using a synthetic route which involves a microwave irradiation promoted Ulmann synthesis. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

18.
Summary Somatic chromosomes of two cultivais of Cajanus cajan, eight species of Atylosia (A. albicans, A. cajanifolia, A. lineata, A. platycarpa, A. scarabaeoides, A. serica, A. trinervia and A. volubilis), and of Rhynchosia rothii were analysed. All species had 2n=22. Eight of the 10 species studied had two pairs of satchromosomes while A. scarabaeoides and A. sericea had only one sat-chromosome pair. Based on relative chromosome length (L%), arm ratio (pa-value) and presence or absence of secondary constriction, a karyotype formula for each species was formulated. Based on these parameters the chromosome pairs could also be assigned to groups ranging from 8 to 10 in different species. Except for the asymmetrical karyotype of A. albicans, the other species had rather moderately symmetrical karyotypes.  相似文献   

19.
James C. Zech 《Brittonia》1999,51(4):415-421
Flavonoid chemistry of the genusMulinum and selected Mulineae taxa was studied. Both flavones and flavonols were identified as C- and O-glycosides. AllMulinum species contain 6,8-di-C-glycosyl chrysoeriol (flavone) and, with the exception of one, quercetin (flavonol). The presence of both flavones and flavonols in this genus weakens previous generalizations that the mulineae contain only flavonols and are primitive compared to other Apiaceae tribes. Based on the selected taxa studied,Azorella appears to differ from bothMulinum andGymnophyton in producing more kinds of flavonols, andGymnophyton appears similar toMulinum in the production of both chrysoeriol and quercetin as well as relatively few compounds. The flavonoid profile ofAsteriscium glaucum is reported as well. In general, a more homogeneous flavonoid compound composition for the Apiaceae is suggested.  相似文献   

20.
An evaluation of the reliability of the Emotions Profile Index (EPI), primate form, was carried out using two captive species of Old World monkeys (Papio hamadryas andMacaca fuscata) and two species (?) of New World monkeys (Saimiri sciureus andS. boliviensis). Observers, some familiar with the animals and some unfamiliar, rated members of the four groups at different times. Inter-rater reliability was high for most members of all species, but only when the observers were familiar with the animals. Assessments remained stable over at least one year.  相似文献   

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