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1.
Arabis glabra (L.)Bernh. var.pseudoturritis (Boiss. & Heldr.)Fiori (till now treated as a separate Mediterranean species:Arabis pseudoturritis Boiss. & Heldr.) differs fromA. glabra var.glabra only in the larger ± pleurorhizal seeds with a ± conspicuous wing that are arranged in one row in each loculus of the (sometimes longer) pods, the pedicels of the siliquae being shorter than in var.glabra. These closely correlated characters are of little systematic relevance according to biometrical and statistical analyses of both taxa and their experimental hybrids. Furthermore, there is correspondence in pod septum anatomy and chromosome number (2n = 12). This, the lack of intrinsic crossing barriers and sympatric occurence (outside the Mediterranean area!) in North America confirm the classification of these taxa as varieties withinA. glabra. Obviously, the seed and fruit characters discussed, are of even less value as generic characters for a separate genus Turritis (comprising Turritisglabra L.).
Herrn Univ.-Prof. Dr.Hermann Merxmüller anläßlich der Vollendung seines 60. Lebensjahres gewidmet.  相似文献   

2.
Chloroplast DNA restriction fragment length polymorphisms have been used to reconstruct the maternal phylogeny of all the known taxa in the small neotropical legume genusLeucaena. Three major plastome clades were recognized, but these did not conform with relationships between the taxa proposed on other characters from morphology, cytology or hybridization. The maternal parentage of tetraploids within the genus has been proposed. Evidence for introgression was found between diploidL. diversifolia and tetraploidL. diversifolia. The implications of these results for the origin of the cultivated taxa are discussed.  相似文献   

3.
The trisaccharide 2-(p-trifluoroacetamidophenyl)ethyl 2-O-(-l-fucopyranosyl)-3-O-(-d-galactopyranosyl)--d-galactopyranoside, corresponding to the human blood group B determinant, was synthesized. Thioglycosides activated by sulfuryl chloride/trifluoromethanesulfonic acid were used as glycosyl donors in the construction of the three glycosidic linkages.  相似文献   

4.
The flowers ofValerianella andFedia are compared in regard to their morphology and anatomy. Characters are typified and utilized for an improved systematic grouping. Informations on flower development, flower and reproductive biology are summarized and supplemented. The phylogeny of several traits is discussed.
2. Teil einer Publikationsserie Beiträge zur Systematik und Evolution vonValerianella undFedia (Valerianaceae) (vgl.Ernet 1977a).  相似文献   

5.
Maria Bokern  Dieter Strack 《Planta》1988,174(1):101-105
Protein preparations from cell suspension cultures of Chenopodium rubrum L. and petals of Lampranthus sociorum (L.Bol.) N.E.Br. (Mes.C.L.Bol.) catalyzed the formation of acylated betacyanins, i.e. celosianin I and II (p-coumaroyl-and feruloylamaranthins) and lampranthin I and II (p-coumaroyl- and feruloylbetanins), from 1-O-(p-coumaroyl)-and 1-O-feruloyl--glucoses as acyldonors and the respective acceptor molecules amaranthin (betanidin 5-O-sophorobiuronic acid = betanidin 5-O--[12]-glucuronosyl--glucoside) and betanin (betanidin 5-O--glucoside). The enzymes involved could generally be classified as 1-O-hydroxycinnamoyl--glucose:betanidinglycoside O-hydroxycinnamoyltransferases (EC 2.3.1.-).Abbreviations HCA hydroxycinnamic acid - HCA hydroxycinnamoyl (=hydroxycinnamic acid-ester moiety) - HPLC high-performance liquid chromatography - TLC thin-layer chromatography  相似文献   

6.
Erika Post 《Hydrobiologia》1966,27(1-2):109-112
Zusammenfassung Ausser dem (west-) pazifischen Hauptareal: Singapur, Sumatra, Borneo, Ambon, Aru-Inseln, W.-Neuguinea, hat die tropische, recht seltene Caloglossa stipitata im Atlantik etwa zwischen den Wendekreisen ein langgestrecktes Nebenareal, dem auch die zwei Ecuador-Standorte Huataco und Esmeraldas zugehören. Neu ist C. stipitata Post für ihr nördlichstes Vorkommen auf Key West-Florida bei 24 1/2° n. Br., (leg. S. Ashmead winter 1855/56) wie den südlichsten, ostbrasilianischen Standort am inland sea channel Mar de Cubãtao/Cananeia bei 24°58 s. Br. (leg. K. Hosoe 5.V.1953 sôbre raizes de Rhizophora).
Caloglossa stipitata in Florida
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7.
We have shown that mercury affects energy transfer in Spirulina platensis. It inhibits energy transfer from phycocyanin to chlorophyll a by specifically bleaching the -84 chromophore of the chromo protein, phycocyanin (PC), in the cyanobacterium. This effect is observed during short-term exposure of cells to Hg2+ ions. Upon long-term (12 h) exposure, mercury at low concentrations (1–2.5 m) causes the gradual degradation of the polypeptide (22 kDa) of the PC of phycobilisomes in this cyanobacterium. The effect of mercury on this polypeptide is significant compared with the other phycobiliproteins.  相似文献   

8.
Schizosaccharomyces pombe cells grow on d-gluconate as the sole carbon and energy source. d-Gluconate is taken up in symport with protons by a specific symporter, pH being the sole driving force. d-Gluconate uptake is independent of the sugar transporting system (e.g. for d-glucose) and of . The carrier is expressed constitutively, and its activity is not subject to glucose repression. Hence, d-gluconate is a suitable carbon and energy source for growth, when d-glucose or other hexoses have to be eliminated e.g. for selection of mutants deficient in hexose transport.Abbreviations 2-DG 2-deoxy-d-glucose - CCCP carbonylcyanide m-chlorophenylhydrazone - pH pH-gradient - electrical potential difference across the plasma membrane - SD standard deviation - SEM standard error of the mean - TPP+ tetraphenylphosphonium  相似文献   

9.
Cell-free extracts from Rhus typhina L. (staghorn sumach) leaves were found to catalyze the transfer of the galloyl moiety of -glucogallin (1-O-galloyl--D-glucose) to 1,6-di-O-galloyl--D-glucose, resulting in the specific formation of 1,2,6-tri-O-galloyl--D-glucose, an intermediate of gallotannin biosynthesis. The reaction product was unequivocally identified by co-chromatography with authentic references using reversed-phase high-performance liquid chromatography and by 1H-nuclear-magnetic-resonance spectroscopy.Abbreviations HPLC high-performance liquid chromatography - NMR nuclear magnetic resonance  相似文献   

10.
The two characters used byBurtt (1974) to segregate the genusSchizoboea fromDidymocarpus, viz. terminal inflorescence and fruit splitting into 4 valves, have been studied in detail: (a) The terminal inflorescence represents a bracteate florescence (sensuTroll), that is an open thyrse, peculiar because of its only two extremely condensed internodes (basic internode + 1 following internode). Correspondingly, there are only two pairs of bracts from which the lower one only is capable to develop axillary partial florescences, i.e. pair-flowered cymes. Thus, the number of cymes is restricted to 2. Because of the condensed internodes, the inconspicuous bracts, and the densely aggregated flowers the two cymes simulate a unitary, terminal structure. By sympodial (± asymmetrically dichasial) linkage of shoot units, composed of an extended internode, a foliage leaf pair (from the axils of which the consecutive units arise) and the florescence,Schizoboea forms (polytelic) anthocladial shoot systems like some genera of the tribeKlugieae (incl.Loxonieae). (b) The fruit dehisces first loculicidally, then each valve splits into three portions (lateral rib and 2 semivalves). Moreover, the 4 placentae become isolated, thus the old fruit comprises 10 elements forming a loose fascicle.—The segregation ofSchizoboea fromDidymocarpus is supported. Whether the affinity is closer toSaintpaulia (as suspected byBurtt) ot toDidymocarpus, remains undecided: In regard to its shoot and inflorescence organization a morphological derivation is possible from both genera.
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11.
Four aryl-phospho--d-glucosidases were identified in Bacillus subtilis by using 4-methylumbelliferyl-phospho--d-glucopyranoside as a substrate. Two of these enzymes are the products of the bglA and bglH genes, previously suggested to encode aryl-phospho--d-glucosidases, while the other enzymes are encoded by the yckE and ydhP genes. Together, these four genes account for >99.9% of the glucosidase activity in B. subtilis on aryl-phospho--d-glucosides. yckE was expressed at a low and constant level during growth, sporulation, and spore germination, and was not induced by aryl--d-glucosides. ydhP was also not induced by aryl--d-glucosides. However, while ydhP was expressed at only a very low level in exponential-phase cells and germinating spores, this gene was expressed at a higher levels upon entry into the stationary phase of growth. Strains lacking yckE or ydhP exhibited no defects in growth, sporulation, or spore germination or in growth on aryl--d-glucosides. However, a strain lacking bglA, bglH and yckE grew poorly if at all on aryl--d-glucosides as the sole carbon source.Abbreviations MU 4-Methylumbelliferone - MUG 4-Methylumbelliferyl--d-glucopyranoside - MUGal 4-Methylumbelliferyl--d-galactopyranoside - MUG-P 4-Methylumbelliferyl--d-glucopyranoside-6-phosphate  相似文献   

12.
A more precise taxonomic concept ofE. hirtella and its infraspecific synonymy is presented. Its diploid nature (2n = 22) is confirmed. Within the European area ofE. hirtella five different races may be recognised: typical, brandisii, capitulata, Rofan and Bretagne. Taxonomic rank is not yet attributed to these races. The heterogeneous taxonomic assembly E. drosocalyx is disentangled. The type refers to products of hybrid introgression ofE. rostkoviana-characters (long glandular hairs) intoE. minima.
Former contributions of this series areEhrendorfer & Vitek (1984) andGreilhuber & al. (1984).  相似文献   

13.
The trisaccharide 2-(p-trifluoroacetamidophenyl)ethyl 2-acetamido-2-deoxy-4-O-[2-O-(-l-fucopyranosyl)--d-galactopyranosyl]--d-glucopyranoside 1 and the tetrasaccharide 2-(p-trifluoroacetamidophenyl)ethyl 2-acetamido-2-deoxy-3-O-(-l-fucopyranosyl)-4-O-[2-O-(-l-fucopyranosyl)--d-galactopyranosyl]--d-glucopyranoside 2 were synthesized. Thioglycosides, suitably protected, activated directly with methyl trifluoromethanesulfonate or dimethyl(methylthio)sulfonium tetrafluoroborate or activated after bromine treatment with halophilic reagents, were used as glycosyl donors in the construction of the glycosidic linkages.Abbreviations DMTSB dimethyl(methylthio)sulfonium tetrafluoroborate - Phth phthaloyl - MBn p-methoxybenzyl - ClBn p-chlorobenzyl  相似文献   

14.
Zusammenfassung Die Hämolymphe vonPsammechinus miliaris (Echinoidea) enthält zwei Hämocytenarten: Die Phagocyten und die Eleocyten. Alle Stadien der aus einer geißeltragenden Jugendform hervorgehenden Phagocyten besitzen gleichartige Feinstrukturen. Diese Zellen können Plasmodien mit breiten, schwingenden Pseudopodienschleiern bilden, mit deren Hilfe Fremdmaterial, aber auch intakte Eleocyten eingefangen und phagocytiert werden. Die Eleocyten treten in zwei Varianten auf: Die roten Eleocyten transportieren in membranbegrenzten, vom Golgi-Apparat stammenden Granula das rote Pigment Echinochrom. Die weißen Eleocyten sind als Melanocyten aufzufassen, deren Melanisierungsprozeß gehemmt ist, solange sie sich frei in der Hämolymphe bewegen. Sie enthalten außer einem pyknotischen Kern nur membranbegrenzte Inklusionen, die eine charakteristische Binnenstruktur aufweisen und vom Golgi-Apparat produziert werden.
On the ultrastructure of invertebrate hemocytesVI. On the hemocytes ofPsammechinus miliaris (Echinoidea)
Summary The hemolymph ofPsammechinus miliaris (Echinoidea) contains two cell types: The phagocytes and the eleocytes. The phagocytes originate from flagellated stem cells and exhibit in all stages of their development similar ultrastructural features. They form plasmodial aggregations and possess undulating veil-like pseudopodia, enabling the cells to catch and to ingest not only foreign material, but also intact eleocytes. The eleocytes appear in two variants: In the red eleocytes a red pigment, echinochrome, is localized in membrane-bounded granules, which originate from the Golgi apparatus. The white eleocytes are identical with melanocytes the melanization of which is inhibited while they are free floating in the hemolymph. They contain a pycnotic nucleus and characteristic inclusions which are produced in the Golgi apparatus.
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15.
Ajuga piskoi Degen & Baldacci, hitherto known only from the type locality in Albania, has been found in Southern Yugoslavia. Two figures are presented. It is a rare and threatened plant species.
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16.
Summary According to the program Palynological Italian Flora, Aeropalynological section, the pollen morphological card ofPinus pinea L. is presented. The study is carried out on pollen coming from three Italian localities and regards fresh and acetolyzed pollen. For each sample, measurements are carried out on 30 fresh pollen grains in glicerol jelly with fuchsin and on 30 acetolyzed pollen grains in water/glicerol (1/1); general observations regard 1000 fresh and 1000 acetolyzed pollen grains/sample. Some observations on the main differences between fresh and acetolyzed pollen are mentioned.
Riassunto Nell'ambito della Flora Palinologica Italiana, Sezione Aeropalinologica, è presentata la scheda morfopalinologica diPinus pinea L. nella versione su polline fresco e polline acetolizzato, su tre campioni di diversa provenienza. Vengono notate le principali differenze tra polline fresco e polline acetolizzato.
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17.
Summary The osmotic potentials of needles were compared from numerous trees that had been classified according to needle loss along an altitude profile. With the increasing degree of damage of the trees, the maximum and minimum values deviated more strongly above and below the common mean of all samples. The level of water content of the needles unequivocally reflected the vitality of the trees. Experiments covering a whole vegetation period were performed on a tree pair selected from a natural stand. They were designed to demonstrate differences in water balance between the healthy and damaged state of the trees. For the damaged tree, measurements of the water potentials of single needles showed a greater reduction of potential during the course of the day compared to the healthy tree. Recovery in the evenings was slower and often incomplete. The osmotic potentials of damaged and healthy shoots measured in individual needles also differed both predawn and especially after transpiration stress. Depending on weather and soil desiccation, the differences were more or less pronounced. In the damaged tree, the rises in potential after saturation of the twigs fell far short of the healthy tree. Reduction of water potential, osmotic potential and relative water content under comparable stress conditions suggest a reduced tolerance of drought by damaged trees. In the context of earlier experiments this result was ascribed to a lack of stomatal control, and long-term pollution effects were thus explained as a specific disturbance of hydroregulation.  相似文献   

18.
Zusammenfassung Der Carnitinstoffwechsel und einige Beziehungen zum Fettsäurestoffwechsel wurden mittels der Wachstumskontrolle, der Bestimmung von Metaboliten und des Nachweises von Enzymaktivitäten in Pseudomonas putida untersucht. Der Stamm wuchs auf -Butyrobetain, D,L-und L-Carnitin, Glycinbetain, Cholin, D,L-Norcarnitin, D,L--Amino--hydroxybutyrat und D,L--Hydroxybutyrat. Obwohl der Stamm unverzweigte Fettsäuren von 2–16 C-Atomen zu untzen vermag, konnte er nur auf O-Acyl-L-carnitinen von 10 oder mehr C-Atomen in der Acylgruppe wachsen. Zugabe von Carnitin stimulierte das Wachstum auf langkettigen Fettsäuren.Die Bildung von Trimethylamin stieg, wenn Carnitin oder -Butyrobetain nur C-Quellen waren, und sank, wenn diese Trimethylammoniumverbindungen sowohl C-als auch N-Quellen waren. L-Carnitin induzierte sowohl die Carnitindehydrogenase als auch die -Hydroxybutyratdehydrogenase. -Butyrobetain als C-und N-Quelle induzierte ebenfalls die Carnitindehydrogenase. Im Rohextrakt betrug die spezifische Aktivität der -Hydroxybutyratdehydrogenase entsprechend dem Wachstum auf L-Carnitin oder D,L--Hydroxybutyrat 0,7 oder 1,6 Mol · min-1 · mg-1. Glycinbetain, Glucose und langkettige Fettsäuren reprimierten die Synthese beider Enzyme. Abhängig von der N-Quelle wird L-Carnitin offensichtlich auf zwei unterschiedlichen Stoffwechselwegen abgebaut.
Interrelationships between carnitine metabolism and fatty acid assimilation in Pseudomonas putida
The carnitine metabolism and some relations to the fatty acid metabolism were studied in Pseudomonas putida by means of control of growth, analysis of metabolites, and determination of enzyme activities. The strain grew on -butyrobetaine, D,L-and L-carnitine, glycinebetaine, choline, D,L-norcarnitine, D,L--amino--hydroxybutyrate, and D,L--hydroxybutyrate. Although the strain used straight-chain fatty acids of 2–16 C-atoms, it was only able to grow on O-acyl-L-carnitines of 10 or more C-atoms in the acylgroup. Addition of carnitine stimulated the growth on long-chain fatty acids.The formation of trimethylamine increased, if L-carnitine or -butyrobetaine were the only carbon sources, and decreased, if these trimethylammonium compounds were carbon as well as nitrogen sources. L-Carnitine induced the carnitine dehydrogenase as well as the -hydroxybutyrate dehydrogenase. -Butyrobetaine as carbon and nitrogen source induced the carnitine dehydrogenase, too. In the crude extract the specific activities of -hydroxybutyrate dehydrogenase were 0.7 or 1.6 moles·min-1·mg-1 after growth on L-carnitine and D,L--hydroxybutyrate, respectively. The synthesis of both enzymes was repressed by glycinebetaine, glucose and long-chain fatty acids. Dependent on the nitrogen source L-carnitine was catabolized via two different pathways.
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19.
We demonstrate that 9-amino-NeuAc transferred to asialo-1-acid glycoprotein resists cleavage by bacterial, viral and mammalian sialidases. This is the first synthetic sialic acid analogue, which can be activated and transferred to glycoprotein, but is not a sialidase (EC 3.2.1.18) substrate.Abbreviations HPLC high performance liquid chromatography - BSA bovine serum albumin - NeuAc N-acetyl-d-neuraminic acid, 5-acetamido-3,5-dideoxy-d-glycero-d-galacto-non-2-ulosonic acid - 9-Amino-NeuAc 9-amino-5-N-acetyl-d-neuraminic acid, 5-acetamido-9-trideoxy-d-glycero-d-galacto-non-2-ulosonic acid - CMP-NeuAc cytidine-5-monophospho-N-acetyl-d-neuraminic acid - CMP-9-amino-NeuAc cytidine-5-monophospho-9-amino-5-N-acetyl-d-neuraminic acid - 9-azido-NeuAc 5-acetamido-9-azido-3,5,9-trideoxy-d-glycero-d-galacto-non-2-ulosonic acid. Enzymes EC 3.2.1.18 sialidase, acylneuraminylhydrolase - EC 2.4.99.1 Galß1-4GlcNAc a(2-6)-sialytransferase  相似文献   

20.
Shoot tips of Triticum aestivum L. cvs. Turbo and Nandu, both summer wheat varieties, were excised from 4 and 10 day-old seedlings, and used for induction of embryogenic callus. A modified L3 medium, supplemented with 10 M 2,4-dichlorophenoxyacetic acid (2,4-d) for culture initiation, and 5 M 2,4-d for subculturing, was optimal; 90% of 4 day-old Turbo seedlings formed embryogenic callus. Optimal plant regeneration was achieved from callus incubated on a modified MS medium without 2,4-d, but supplemented with 2.22 M 6-benzylaminopurine and 0.27 M naphthaleneacetic acid. Plantlets formed via embryogenesis from all embryogenic Turbo calli initiated from 4 day-old explants, with a mean number of 8 regenerants per explant. Regeneration occured via embryogenesis only. Results obtained using Nandu were within the same range.Abbreviations BA 6-benzylaminopurine - 2,4-d 2,4-dichlorophenoxyacetic acid - NAA naphthaleneacetic acid  相似文献   

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