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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.
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.
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3.
The new genus and species Teracosphaeria petroica is described for a perithecial ascomycete and its anamorph occurring on decayed wood collected in New Zealand. The fungus produces immersed, non-stromatic ceratosphaeria-like perithecia in nature, with hyaline, septate ascospores produced in unitunicate, non-amyloid asci. The anamorph produced in vitro is phialophora-like with lightly pigmented phialides terminating in flaring, deep collarettes that are often noticeably brown with conspicuous periclinal thickening. Phylogenetic analysis of LSU rDNA sequence data indicates that this fungus is distinct from morphologically similar fungi classified in the Chaetosphaeriales, the Trichosphaeriales or the Magnaporthaceae. It forms a monophyletic group with recently described, chaetosphaeria-like ascomycetes, such as the pyrenomycete genus Mirannulata, and shows affinity with the anamorphic species Dictyochaeta cylindrospora. The usefulness of describing anamorph genera for morphologically reduced anamorphs, when anamorph characteristics are actually part of the holomorph diagnosis, is discussed. An apparently contradictory example of the so-called Cordana and Pseudobotrytis anamorphs of Porosphaerella spp. is also discussed.  相似文献   

4.
The taxonomic positions ofRetzia, Desfontainia, andNicodemia have been much discussed, and all three genera have been included inLoganiaceae (Gentianales). We have made a cladistic analysis ofrbcL gene sequences to determine the relationships of these taxa toGentianales. Four newrbcL sequences are presented; i.e., ofRetzia, Desfontainia, Diervilla (Caprifoliaceae), andEuthystachys (Stilbaceae). Our results show thatRetzia, Desfontainia, andNicodemia are not closely related toLoganiaceae or theGentianales. Retzia is most closely related toEuthystachys and is better included inStilbaceae. The positions ofDesfontainia andNicodemia are not settled, butDesfontainia shows affinity for theDipsacales s.l. andNicodemia for theLamiales s.l.  相似文献   

5.
Intima-media of porcine thoracic aorta were digested with pronase, after extraction of the saline-soluble matters and fat. A glycopeptide fraction was precipitated with 90% (vol/vol) ethanol from the 80% ethanol-soluble fraction of the trichloroacetic acid (7%)-soluble fraction of the pronase digest. The glycopeptide fraction was fractionated by affinity chromatography on concanavalin A (Con A)-Sepharose 4B, yielding 4 fractions (FA, FB, FC and FD). The most carbohydrate-rich fraction (FB) was further purified to a homogeneous state. The purified FB (FB-0.1) and all other fractions contained desmosine and isodesmosine. The major sugars in the fractions without or with low affinity for Con A (FA, FB, and FB-0.1) were glucosamine, galactose, mannose and sialic acid, while those in the fractions with high affinity for this lectin (FC and FD) were glucosamine, glucose and mannose. All the fractions contained glycine, aspartic acid (and/or asparagine), serine, proline, threonine, glutamic acid (and/or glutamine) and alanine as the major amino acids, amounting to approximately 80% of the total.  相似文献   

6.
The geographic range and bloom frequency of the toxic dinoflagellate Alexandrium minutum and other members of the A. minutum group have been increasing over the past few decades. Some of these species are responsible for paralytic shellfish poisoning (PSP) outbreaks throughout the world. The origins of new toxic populations found in previously unaffected areas are typically not known due to a lack of reliable plankton records with sound species identifications and to the lack of a global genetic database. This paper provides the first comprehensive study of minutum-group morphology and phylogeny on a global scale, including 45 isolates from northern Europe, the Mediterranean, Asia, Australia and New Zealand.Neither the morphospecies Alexandrium lusitanicum nor A. angustitabulatum was recoverable morphologically, due to large variation within and among all minutum-group clonal strains in characters previously used to distinguish these species: the length:width of the anterior sulcal plate, shape of the 1′ plate, connection between the 1′ plate and the apical pore complex, and the presence of a ventral pore. DNA sequence data from the D1 to D2 region of the LSU rDNA also fail to recognize these species. Therefore, we recommend that all isolates previously designated as A. lusitanicum or A. angustitabulatum be redesignated as A. minutum. A. tamutum, A. insuetum, and A. andersonii are clearly different from A. minutum on the basis of both genetic and morphological data.A. minutum strains from Europe and Australia are closely related to one another, which may indicate an introduction from Europe to Australia given the long history of PSP in Europe and its recent occurrence in Australia. A minutum from New Zealand and Taiwan form a separate phylogenetic group. Most strains of A. minutum fit into one of these two groups, although there are a few outlying strains that merit further study and may represent new species. The results of this paper have greatly improved our ability to track the spread of A. minutum species and to understand the evolutionary relationships within the A. minutum group by correcting inaccurate taxonomy and providing a global genetic database.  相似文献   

7.
Analyses of New World skeletal populations for the presence of erosions and other osseous alterations and their character, distribution, and radiologic appearance shows that osteoarthritis is predominantly a disease of animals raised in artificially constrained environments. Primary calcium pyrophosphate deposition disease (CPPD) was also found only in artificially constrained animals, although hyperparathyroidism (overproduction of parathyroid hormone) may have been responsible. CPPD was observed once as a secondary phenomenon, complicating another form of arthritis in free-ranging animals. Limited in occurrence to two genera,Alouatta andCebus, the frequency of spondyloarthropathy was similar to that noted in humans and significantly lower than that observed in gorillas and chimpanzees. The many dichotomies ofCebus andAlouatta place them almost at opposite ends of the New World monkey spectrum, making a common susceptibility factor difficult to identify.  相似文献   

8.
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   

9.
10.
A skull fragment (VM-0) from Orce, Granada, Spain, dated palaeomagnetically at about 1.6 Myr, is thought by some palaeontologist to be hominid, while others maintain it is equid. If hominid, it would be by far the oldest evidence ofHomo in Europe. Immunological studies on residual albumin in this fossil were carried out independently, and with different immunological methods, at the University of California, San Francisco (radioimmunoassay), and at the University of Granada, Spain (enzyme immunoassay). Other fossils attributed to hominids also studied wereVM1960 from Venta Micena, andCV-1 from Cueva Victoria, Murcia, Spain. Undisputed equid and bovid fossils from the same deposits and dated to a similar period as the Orce skull were also analyzed. Our results showed that species-specific albumin can be detected in 1.6 Myr-old hominid, equid and bovid fossils. The albumin from the Orce skull fragment and fromVM-1960 was immunologically closer to human albumin. These findings support the contention that theVM-0 andVM-1960 are hominid and that members of the genusHomo occupied southern Spain 1.6 Myr ago.  相似文献   

11.
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   

12.
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   

13.
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   

14.
The adult morphology of the Australian Limnadopsis shows some remarkable differences to that of other Limnadiidae. These differences are not reflected in its larval development. In Limnadopsis parvispinus, larval development comprises six stages. In stages I and II only the three naupliar appendages are present: the antennule as a small bud, the biramous antenna as the main swimming organ, and the mandible. The antennal protopod bears two endites, the proximal naupliar process and a more distal endite. In stage III a bifid naupliar process (in earlier stages not bifid) and the first signs of the carapace and trunk limb anlagen (undifferentiated rudiments) appear. In stage IV the carapace anlagen become more pronounced. The number of trunk limb anlagens increases to five, and differentiation has commenced. In stage V the first five pairs of trunk limbs are differentiated to varying degrees. The anterior-most four pairs of trunk limbs are subdivided into five endites, a small endopod, an exopod and an epipod. The bivalved carapace covers the anterior-most limbs. In larval stage VI the carapace is larger and the trunk limbs are further differentiated. A general pattern in the sequence of larval stages is the increasing number of sensilla on the antennules. From the last larval to the first postlarval stage, a significant change in morphology takes place. The trunk limbs are now used for swimming. Typical larval organs are much smaller than in the last larval stage. A comparison with other representatives of the Limnadiidae shows a high degree of correspondence, with most differences explained by the heterochronous appearance of characters during development. Five to seven stages are described for all studied Limnadiidae, including one particular stage in which four fully developed setae, a bifid naupliar process and the first signs of carapace anlagen are present. These characters are found in stage III in L. parvispinus, Limnadia stanleyana, Eulimnadia texana, and Imnadia yeyetta but in stage IV in E. braueriana and L. lenticularis. Based on a comparison of the larval stages of six limnadiid and one cyzicid species, we conclude that at least six naupliar stages belong to the limnadiid ground pattern.  相似文献   

15.
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   

16.
Paraveinal mesophyll (PVM) is a distinctive anatomical feature of the leaf mesophyll of some plant taxa that may represent a specialized physiological compartment. A comprehensive review of the 42 published references that mention PVM or similar cell layers and a survey of 121 of the 272 species of all nine genera of thePhaseoleae subtribeErythrininae demonstrate that PVM is nearly exclusively found inLeguminosae. InLeguminosae, PVM is either rare or absent in subfamilyCaesalpinioideae, uncommon inMimosoideae, and extensively distributed amongPapilionoideae. In subtribeErythrininae, PVM is ubiquitous inErythrina, and occurs in four other genera. ThreeErythrininae genera (Apios, Mucuna, andCochlianthus) lack PVM. Unique chloroplast-poor, enlarged conical cells (pellucid palisade idioblasts) occur in 80 species ofErythrina but not in any other genus ofErythrininae.  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.
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   

19.
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   

20.
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