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1.
Summary We have constructedspo0A-lacZ andspo0F-lacZ fusions with a temperate phage vector and have investigated howspo0 gene products are involved in the expression of each of these genes. The expression ofspo0A-lacZ andspo0F-lacZ was stimulated at about the time of cessation of vegetative growth in Spo+ cells. This stimulation ofspo0A-lacZ was impaired by mutations in thespo0B, D, E, F orH genes but was not affected by mutations in thespo0J orK genes. Similar results were obtained with thespo0F-lacZ fusion. The effect of thespo0A mutation onspo0A-lacZ expression was characteristic: thespo0A-directed β-galactosidase activity found during vegetative growth was significantly enhanced in thespo0A mutant. This result suggests thatspo0A gene expression is autoregulated being repressed by its own gene product. Another remarkable observation was the effect of thesof-1 mutation, which is known to be aspo0A allele; it suppressed the sporulation deficiency ofspo0B, spo0D andspo0F mutants. Thespo0A-lacZ stimulation, which is impaired by any one of thesespo0 mutations, was restored by the additionalsof-1 mutation.  相似文献   

2.
Oligosaccharides from theO-polysaccharide chain of theSalmonella typhi 253Ty lipopolysaccharide (LPS) were prepared from delipidated LPS by digestion with bacteriophage P22. The oligosaccharides were separated by gel chromatography into fractions representing monomers to polymers of the basic tetrasaccharide repeating unit. Fractions containing the dimer and the trimer were analysed by fast atom bombardment-mass spectrometry as methylated alditols. The mass spectra clearly showed heterogeneity in terms ofd-glucose substitution of thed-galactose residue in the tetrasaccharide repeating unit: dimers with none, one, or twod-glucosyl branches and trimers with none, one, two, or threed-glucosyl branches were found. This suggests a randomd-glucosylation of theO-polysaccharide chain ofS. typhi 253Ty.  相似文献   

3.
A comparison of the West AfricanNeoschumannia Schltr. and the East AfricanSwynnertonia S. Moore reveals that the two monotypic genera must be united.Swynnertonia is sunk into synonymy ofNeoschumannia and the new combinationNeoschumannia cardinea (S. Moore)Meve is made for the East African species.Neoschumannia is shown to belong to the tribeStapelieae. The taxon exhibits a very unusual character combination: the growth form of a woody liana is combined with a tripartite corona unique within theAsclepiadaceae. The morphology of the corona suggests a position ofNeoschumannia close to the base of theStapelieaeCeropegiinae alliance.  相似文献   

4.
Intergeneric crosses were made between representatives of the genomically-defined generaElymus, Agropyron, Elytrigia, Pseudoroegneria, andThinopyrum. The genomic constitution ofElytrigia repens, the type species ofElytrigia, is shown to be SSH, a genomic combination otherwise found only inElymus. The S genome ofPseudoroegneria has almost always a dominant influence on the morphology of the taxa of which it is a component.Wang (1989) showed that the J genome inThinopyrum and the S genome have considerable homoeology, with a mean c-value of 0.35 in diploid SJ hybrids. A genetic coherence from S to SJe, Je, JeJb, and Jb can be expected, agreeing with the continuous morphologic variation pattern observed. Because of the absence of morphological discontinuities between the taxa,Pseudoroegneria (S),Elymus (SH, SY, sometimes with additional genomes),Elytrigia (SSH, SSHX), andThinopyrum (SJ, SJJ, J) are best treated as a single genus,Elymus, following the generic concept ofMelderis in Flora Europaea and Flora of Turkey. The basic genomic constituents ofElymus will then be the S and/or J genomes.Agropyron, with diploids, tetraploids, and hexaploids based on the P genome is morphologically distinct from other genera inTriticeae. In a few species ofElymus andPseudoroegneria, a P genome is an additional constituent. In these cases the P genome has a negligible morphological influence. Therefore, it seems reasonable to maintainAgropyron as a separate genus.  相似文献   

5.
TheSimaroubaceae generally have no true stipules. The stipule-like appendages of some genera proved to be pseudo- or metastipules (Weberling & Leenhouts 1965). There seem to be some exceptions, however: the generaCadellia (incl.Guilfoylia) andRecchia on the one hand, and theIrvingioideae on the other. As these taxa, with exception ofRecchia, have simple leaves, there are no indications that their stipule-like appendages might be pseudo- or metastipules. In regard to their position and ontogeny these appendages behave completely like true stipules. Assuming the view ofForman, one could conceive a morphological line from the long, broadly inserted axillary stipules of mostIrvingioideae to the small scaly triangular stipules ofIxonanthoideae. The similarities between the stipules ofIrvingioideae andErythroxylaceae (already emphasized byHallier and others), become even more evident when their ontogeny is investigated. TheIrvingioideae, therefore, might be regarded as a separate family (perhaps with some relation to theErythroxylaceae,Hallier) or as a subfamily ofIxonanthaceae (Forman).—In addition to data on stipules some results on the palynology and shoot anatomy of the generaCadellia (incl.Guilfoylia) andRecchia are reported. Their relationship with theSimaroubaceae also appears doubtful. If they are to be included, they represent a somewhat isolated group near the base of the family which otherwise has lost its stipules.
Herrn Univ.-Prof. Dr.Walter Leinfellner zum 70. Geburtstag gewidmet.  相似文献   

6.
The floral anatomy of four species ofViviania has been studied. In the basic floral plan and essential floral anatomical featuresViviana closely resembles theGeraniaceae. Evidence from vegetative and floral anatomy, ultrastructural studies on phloem as well as phytochemistry supports geranialean affinity ofViviania; the placement within thePittosporales sensuHutchinson being unnatural.  相似文献   

7.
Roots ofHectorella caespitosa Hook. f. were induced to produce a red pigment which was shown to be a betalain and not an anthocyanin. These data indicate thatHectorella belongs to theChenopodiineae, the betalain suborder of theCentrospermae, and excludes alignment with the anthocyanin family theCaryophyllaceae.  相似文献   

8.
A parsimony analysis of DNA sequences of the chloroplast-encoded generbcL from twelve members of theAcanthaceae s.l., including members of the sometimes segregateThunbergioideae andNelsonioideae, and other families in theBignoniales sensuThorne (1992) is presented. The results largely agree with the classification of theAcanthaceae presented byBremekamp (1965) andThorne (1992) and supportNelsonioideae as a sister group to the rest of theAcanthaceae. Thunbergioideae are placed as a sister toAcanthaceae s.str.Acanthus andAphelandra, both representatives ofAcanthoideae, form a sister group toRuellioideae. An analysis of branch support found that many branches throughout theBignoniales are weakly upheld. This points to the need for further studies in the group using more sequences ofrbcL as well as other data. None of the families ofBignoniales as presently circumscribed (includingAcanthaceae s.l.) were strongly supported, although the larger clade containing the families of theBignoniales was robust.  相似文献   

9.
The serological investigations support the opinion ofJanchen (1942) to combine the generaBunias, Isatis, andSisymbrium in the tribeSisymbrieae; Cheiranthus, Erysimum, andMatthiola in the tribeHesperideae; andBrassica, Crambe, Sinapis, andSuccowia in the tribeBrassiceae. They further underline the central position of theSisymbrieae and the isolated position of theHeliophileae. In accordance withEigner (1973) theBrassiceae are placed closer to theSisymbrieae than inJanchen; the same holds for thePringleeae. No serological justification could be found to uniteArabis andBarbarea in the tribeArabideae, andAlyssum andLunaria in theAlysseae. From the antigen-systems used among the representatives ofJanchen's Lepidieae the generaLepidium andNeslia show remarkable correspondence both toCamelina andThlaspi, but not toCochlearia which appears distant fromCamelina andThlaspi also.
Teil 1/Part 1.  相似文献   

10.
A phylogenetic analysis of theUlmaceae, Cannabaceae, Barbeyaceae, andBroussonetia of theMoraceae produced nine equally parsimonious trees with 127 steps. TheUlmoideae (Ulmaceae, sensuGrudzinskaya) are a monophyletic group and distinct from theCeltidoideae. The genusAmpelocera occupies an isolated taxonomic position among the celtidoids. The similarity ofAmpelocera to the fossil celtidoid flowerEoceltis of North America suggests thatAmpelocera posesses an archaic suite of characters, and occupies a primitive position among the celtidoids, theCannabaceae and theMoraceae. The relationships among the other celtidoid taxa,Cannabaceae, andBroussonetia are problematic. TheCannabaceae andBroussonetia of theMoraceae are nested within the celtidoids suggesting that this is a paraphyletic group. The close, but unresolved, relationship of the celtidoids to theMoraceae andCannabaceae observed in this analysis, and the appearance of the celtidoids in the fossil record prior to the ulmoids suggests that the evolutionary relationship of the ulmoids and celtidoids may be more distant than current taxonomic treatments reflect.  相似文献   

11.
The anatomy, chemistry and developmental morphology ofAnamylopsora pulcherrima is investigated. Some characters, including the ascus structure, suggest a close affinity with theAgyriaceae. However, the chemistry and the pycnidial structure differ as well as the ascoma ontogeny.Anamylopsora has a gymnocarpous ascoma development and the ascogonia are produced in stipes.Trapelia coarctata, as a typical member of theAgyriaceae, shows a hemiangiocarpous ascoma ontogeny. The anatomical, chemical and ontogenetical characters of several families are compared withAnamylopsora and it is shown that the genus is best placed in a monotypic familyAnamylopsoraceae Lumbsch & Lunke, fam. nova, which is placed in theAgyriineae (Lecanorales).This paper is dedicated to Prof. DrAino Henssen (Marburg) on the occasion of the 70th birthday.  相似文献   

12.
The chemotaxonomic findings relating to the generaBoletinus, Suillus, Gastroboletus, Gomphidius, andChroogomphus are summarized and discussed, using published data as well as our own hitherto unpublished evidence of pigments and chromogens. The study confirms repeatedly made claims that these genera are closely related. In addition to the presence of pigments which are typical for most members of theBoletales (e.g., pulvinic acid derivatives, terphenyl quinones, cyclopentenones), prenylated phenols and quinones can also be constantly detected here (with the exception ofBoletinus), just as inRhizopogon. Accordingly,Suillus is more closely related to theGomphidiaceae andRhizopogonaceae than to the remaining boletes. It is therefore necessary to establish a new family (Suillaceae which includeBoletinus, Suillus, andGastrosuillus) and a new suborder (Suillineae which includeSuillaceae, Gomphidiaceae, andRhizopogonaceae) within theBoletales. Chemosystematics ofBoletales 2. For part 1 seeBesl & al. (1986). Dedicated to emer. Univ.-Prof. DrFriedrich Ehrendorfer on the occasion of his 70th birthday  相似文献   

13.
The hypothesis ofHenriques andFernandes that several Iberian species ofNarcissus (Amaryllidaceae) are tristylous is reconsidered. Contrary to the opinion ofBateman and most subsequent authors, we believe that the available evidence indicates that some populations ofN. triandrus andN. fernandesii, at least, are tristylous; other populations ofN. triandrus are distylous.Hugonia cf.penicillanthemum (Linaceae) from new Caledonia is distylous, but it remains possible that other species ofHugonia are tristylous. The disputed occurrence of heterostyly in S. African species ofBauhinia (Leguminosae),Cleome (Capparaceae) andAneilema (Commelinaceae), and inAgelaea (Connaraceae) is discussed.  相似文献   

14.
A cDNA clone encodingS-adenosyl-L-methionine:trans-caffeoyl-CoA 3-O-methyl-transferase (EC 2.1.1.104; CCoAOMT) fromStellana longipes Goldie (long-stalked chick-weed) was isolated and studied. Structural analysis of both the nucleotide sequence and the predicted amino acid sequence suggests that our cloned sequence encoded a CCoAOMT enzyme ofStellaria longipes, which shared overall structural similarity with other plant CCoAOMTs but exhibited certain distinct characteristics. Southern blot hybridization and cloning analyses indicating a small CCoAOMT gene family in theStellana longipes genome and the absence of introns in the coding region of the cDNA-corresponding gene. Sequence variations in the coding region were found among three genotypes from geographically isolated populations. Higher levels of CCoAOMT mRNA were detected in stems and leaves than in roots. The cDNA-encoded protein expressed inEschendia coli was shown to utilize caffeoyl-CoA, but not caffeic acid or 5-hydroxy ferulic acid, as its substrate.  相似文献   

15.
Summary A serial reconstruction ofPyramimonas gelidicola McFadden, Moestrup andWetherbee has revealed a large reticulated mitochondrion branching throughout the cell. The possibility of single mitochondria in other members of thePrasinophyceae and the uniformity of the morphology of this organelle within the class is discussed.  相似文献   

16.
In 83 species of the familiesMonotropaceae, Apocynaceae, Oleaceae, Scrophulariaceae, Lentibulariaceae, Bignoniaceae, Martyniaceae, Myoporaceae, Verbenaceae, Lamiaceae, Campanulaceae, andLiliaceae, protein bodies in the cell nuclei have been found, in 68 of these species for the first time. On the basis of their structure in accordance with morphological characters the generaBurgsdorfia, Hesiodia, Olisia, andPhlomoides of theLamiaceae are accepted;Lamium is divided intoLamium, Lamiastrum andOrvala; two new combinations are established:Kickxia campyloceras (Rech. fil. &Esfandiari)Speta andEtornotus papilionaceus (Burm. in L.)Speta. Deviating shape or lack of protein bodies corroborate former taxonomic decisions, e.g. the transfer ofMonotropa toMonotropaceae or the separation ofGaleopsis andLadanum; Veronica schmidtiana should not be included inPseudolysimachion. Systematic affinities are discussed primarily withinScrophulariaceae because nuclear protein bodies have been studied already in many species of this family. ForCampanula patula two 2 x populations are reported.
Herrn Professor Dr. L.Geitler zum 80. Geburtstag gewidmet.  相似文献   

17.
Pyrenoid ultrastructure has been investigated from cultures of all 26 species ofTrebouxia with the aim of establishing pyrenoids as a taxonomic character. Different arrangements and forms of thylakoid lamellae within the pyrenoid matrix allow eight pyrenoid types to be distinguished. Each type is characteristic of a group of species. Thegigantea- andimpressa-type are similar, differing only in the form of the tubules: short, branched tubules mark thegigantea-type; ± long and straight invaginations theimpressa-type. Thearboricola-type is characterized by meandering pyrenoid membranes developing from lamellae parallel with each other in young autospores. Pyrenoids of thegelatinosa-type are traversed by thin parallel-arranged tubules. Few thylakoids with a curved profile are typical of theirregularis-type. Thecorticola-type is different from all others in having a distinct starch sheath closely connected with the pyrenoid matrix and no pyrenoglobuli being associated with the pyrenoid membranes. No true pyrenoids have been found inT. magna andT. erici. Within the chloroplast, they have indistinct areas with pyrenoglobuli, but without differentiated thylakoids. Pyrenoid morphology is stable in culture on different media as well as in phycobionts within lichen thalli. Comparing the pyrenoid of a lichenizedTrebouxia with that from cultured species, the identification of the phycobiont within the lichen thallus is possible, without the need of culturing the algae. This has been shown in species ofParmelia andHypogymnia. New aspects for the taxonomy and systematics ofTrebouxia are discussed.Dedicated to Prof. DrLothar Geitler on the occasion of the 90th anniversary of his birthday.  相似文献   

18.
The tribePlucheeae (Benth.)A. Anderb., has been analysed cladistically by means of a computerized parsimony program (Hennig 86), using theArctotideae as outgroup. The results of the analysis are presented in a consensus tree and one cladogram. Four major monophyletic subgroups can be recognized: TheColeocoma group (3 genera), thePterocaulon group (3 genera), theLaggera group (6 genera), and thePluchea group (12 genera). All recognized genera are described and most genera are supplied with taxonomical notes including comments on their taxonomic status. Genera such asBlumea, Pluchea, andEpaltes are demonstrated to be unnatural assemblages.Monarrhenus andTessaria are both closely related to thePluchea complex. The old generic nameLitogyne Harv. has been taken up for one species ofEpaltes, the genusRhodogeron is reduced to a synonym ofSachsia, and the following new combinations are made;Litogyne gariepina (DC.)A. Anderb., andSachsia coronopifolia (Griseb.)A. Anderb.  相似文献   

19.
Restriction site maps and a clone bank of chloroplast DNA (cpDNA) ofMahonia higginsae (Munz)Ahrendt (Berberidaceae) were constructed. The size ofMahonia cpDNA was about 167 kb. Precise mapping using gene probes revealed that cpDNA ofM. higginsae has an inverted repeat (IR) 11.5 kb larger than the tobacco IR. The expansion of the IR into the large single copy region has resulted in the duplication of at least ten genes includingpsbB. The phylogenetic distribution of the expanded IR was examined in twenty-five species ofBerberis andMahonia, twenty species representing the fifteen remaining genera of theBerberidaceae, and four species from four allied families. Our survey indicates that only the species of the closely related generaBerberis andMahonia share the 11.5kb expansion of IR. This result supports their close phylogenetic relationship, which has been suggested previously by chromosomal, morphological, and serological data.  相似文献   

20.
The evolution and taxonomic relationships in theTriticeae are discussed with the view to highlight aspects of this agronomically important group of plants, which may be of interest to molecular biology. Some of these aspects are addressed in more detail in adjoining papers in which specific genomic loci have been examined at the DNA sequence or isozyme level. Aspects discussed include the systematics and geographic distribution of theTriticeae species, isozyme and chromosome pairing studies on some of the species as well as more recent developments in DNA analyses. A survey of the systematics of theTriticeae indicated that the genomic system ofLöve is probably the most useful starting point for interpreting molecular data even though the system has many problems from a taxonomic point of view. The geographical distribution ofTriticeae species, using both published and unpublished data, suggested that information of this type taken together with the theory of continental drift provides a broad time-span for considering data from DNA sequence studies. The significance, and modes of analyses, of isozyme studies were assessed because they often provide valuable characters in determining relationships between species. The main character underlyingLöve's andDewey's analyses of theTriticeae, namely chromosome pairing, is discussed with particular reference to isozyme studies to show that in some cases, such as species ofHordeum sensu lato, consistent relationships are obtained. Finally, new developments in understanding chromosome structure are considered in relation to the above variables in the taxonomy and evolution of theTriticeae.  相似文献   

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