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1.
Cellulomonas cartalyticum was found to contain a peptidoglycan type different from that of the other species ofCellulomonas. The diamino acid is lysine instead of ornithine and the interpeptide bridge consists ofd-Asp-d-Ser. The same peptidoglycan type occurs inCorynebacterium manihot, Brevibacterium liticum andArthrobacter luteus. These non cellulolytic organisms are most likely not closely related withCellulomonas cartalyticum, as indicated by the very different G+C content of their DNA, although they formed a narrow cluster includingC. cartalyticum when numeric taxonomical methods were applied.
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2.
Plempel  Manfred 《Planta》1965,65(3):225-231
Zusammenfassung Gamonbildung und Carotinsynthese sind bei den Zygomyceten Mucor mucedo, Blakeslea trispora und Phycomyces Blakesleeanus gekoppelte Reaktionen. Die Gamonbildung verläuft parallel zur Carotinbiosynthese. Damit kann ein Weg zur Klärung der Gamonsynthese gefunden werden.
Sexual reaction and carotene synthesis in Zygomycetes
Summary In the Zygomycetes Mucor mucedo, Blakeslea trispora and Phycomyces Blakesleeanus, gamon formation and carotene synthesis are coupled reactions. The gamon formation goes parallel with the carotene biosynthesis. This provides a way by which gamon synthesis can be elucidated.
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3.
Zusammenfassung Anhand der Retzius-Streifen und der Doppelbrechung wird bei urodelen (Megalobatrachus japonicus) und anuren (Rana catesbyana) Amphibien die Anwesenheit von Zahnschmelz nachgewiesen; er überzieht als zusammenhängende Kappe den distalen Abschnitt des zweispitzigen Zahnes.
Enamel structure in urodela and anura
Summary The presence of enamel on urodele (Megalobatrachus japonicus) and anuran (Rana catesbyana) teeth has been shown by birefringence and the identification of the stripes (lines) of Retzius. The enamel forms a continuous cap on the distal part of the bicuspid teeth.
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4.
Zusammenfassung Die Arten der Gattungen Ankistrodesmus und Scenedesmus, die sich hinsichtlich Hydrogenase-Aktivität, Bildung von Sekundär-Carotinoiden und Gelatine-Verflüssigung als biochemisch sehr einheitlich erwiesen hatten, zeigen zum Teil beträchtliche Unterschiede in ihrer Säureresistenz (vgl. Tab. 1–4), die somit als taxonomisches Merkmal verwendet werden kann.
Physiological and biochemical contributions to the taxonomy of the genera Ankistrodesmus and Scenedesmus II. Acid tolerance
Summary Some species of the genera Ankistrodesmus and Scendesmus exhibit pronounced differences in acid tolerance (cf. Tables 1–4), in contrast to their biochemical uniformity in hydrogenase activity, formation of secondary carotenoids, and liquefaction of gelatin. Thus acid tolerance can serve as a taxonomic character in these genera.
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5.
Zusammenfassung Markiertes Glycin und Serin wurde in Ferrichrom, Ferricrocin und Ferrichrysin von vier Stämmen der Gattung Aspergillus zu 1,6–11,8% in vivo eingebaut. Von Aspergillus fumigatus und A. quadricinctus wurden zellfreie Extrakte hergestellt, die Cyclohexapeptide synthetisieren können.
Incorporation of glycine and serine in sideramines of the ferrichrome type with fungi of the genus Aspergillus in vivo and in vitro
A 1.6–11.8% incorporation of labelled glycine and serine into ferrichrome, ferricrocin and ferrichrysin has been achieved with four strains of Aspergillus in vivo. Cell-free extracts of Aspergillus fumigatus and A. quadricinctus capable of cyclohexapeptide biosynthesis have been prepared.
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6.
Zusammenfassung In den einfachen epithelialen Nervensystemen des Seesterns Astropecten irregularis und der Enteropneusten Harrimania kupfferi und Ptychodera flava sind Noradrenalin und 5-Hydroxytryptamin fluoreszenzmikroskopisch und mikrospektrofluorimetrisch nachgewiesen worden. Noradrenalin ist bei Astropecten weitgehend auf eine basale Faserschicht des ektoneuralen Systems beschränkt, während 5-HT vor allem apikal verbreitet ist. Fluoreszierende Perikaryen und synapsenartige Verdickungen sind selten und wurden vor allem bei den Enteropneusten gefunden. Vermutlich ist Noradrenalin in erster Linie im sensiblen Anteil der untersuchten Nervensysteme lokalisiert.
Catecholamines and 5-hydroxytryptamine in the starfish and enteropneust nervous systems
Summary Noradrenaline and 5-hydroxytryptamine have been demonstrated with the fluorescence microscope and a microspectrofluorimeter in the primitive epithelial nervous systems of the starfish Astropecten irregularis and the Enteropneusts Harrimania kupfferi and Ptychodera flava. In Astropecten noradrenaline is largely confined to a basal fibre layer in the ectoneural system, 5-HT occurs predominantly in an apical localization. Pericarya and synaptic thickenings emitting a characteristic fluorescence are rare and have been found mainly in the Enteropneust species. Presumably, noradrenaline is predominantly localized in the sensory part of nervous systems investigated.
Herrn Prof. A. G. E. Pearse, Dept. of Histochemistry, und besonders Herrn Dr. F. W. D. Rost, Unit of Microspectrofluorimetry, Royal Postgraduate Medical School, London, danke ich für die Hilfe bei der Benutzung ihrer mikrospektrofluorimetrischen Anlage und des Computers beim Auswerten der Daten.  相似文献   

7.
Viscin threads and other pollen connecting threads of some angiosperm families were investigated, especially those ofEricaceae. According to the definition adopted, viscin threads are ± long exinous processes which consist of exinous material and connect pollen grains or tetrads. Such viscin threads are found within theOnagraceae, Caesalpiniaceae, Ericaceae, andMimosaceae only. While they differ in structure and composition, they always consist of sporopollenin and exhibit a very strong stickiness, even after all viscid substances have been removed by acetolysis. In contrast, the pollen connecting scleroprotein threads ofOrchidaceae and the cellular threads ofStrelitzia reginae Aiton. (Musaceae) are not connected with the exine surface, are destroyed by acetolysis, and thus do not correspond to viscin threads.
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8.
Zusammenfassung Ein asporogener Stamm vonSaccharomyces cerevisiae und sechs Stämme vonLactobacillus brevis bildeten in einem vollsynthetischen Medium Butanol-2 aus Butandiol-2,3. Hierbei wurde meso-Butandiol-2,3 verbraucht. Die verschiedenen Lactobacillen bilden unterschiedliche Mengen an Butanol-2 (bis 810 mg/l).
On the formation of butanol-2 by lactic acid bacteria and yeast
Butanol-2 was formed from butanediol-2,3 in a synthetic medium by an asporogenous strain ofSaccharomyces cerevisiae and 6 strains ofLactobacillus brevis. The mesoform of butanediol-2,3 is degraded to butanol-2. The lactic acid bacteria form different amounts of butanol-2 (up to 810 mg/l).

Abkürzungen r.A. reiner Alkohol  相似文献   

9.
K. Hausmann  B. Walz 《Protoplasma》1979,99(1-2):67-77
Summary In the cytoplasm of the marine ciliateEuplotes vannus, there exist two conspicuous types of membrane bound inclusions: 1. irregularly shaped crystals which are highly anisotropic; 2. globular lithosomes characterized by concentrically arranged layers of deposits which exhibit only faint birefringence. Normally, both structures form distinct accumulations. Energy dispersive X-ray microanalysis of these accumulations reveals a high content of calcium and phosphorus, besides magnesium, sulphur and chlorine. Analysis of cell areas devoid of the inclusions show significantly lower calcium- and phosphorus-peaks.
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10.
The pollenkitt ofTilia platyphyllos andT. tomentosa is produced during the tetrade-stage by the tapetum plastides. After tapetum degeneration pollenkitt and accompanying substances are deposited predominantly in the intrabacular spaces of the exine, and only in small quantities on the surface of the exine itself.
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11.
As a rule,Gentianaceae exhibit a double unilacunar nodal pattern. Upon leaving the lacun, the complex leaf trace divides first into three branches, and then into five or more bundles which become the leaf veins. OnlyGentiana lutea (andG. punctata) as well asMenyanthes trifoliata differ from all other species investigated by their multilacunar nodes. BothCentaurium andOrphium within the cortex form a completely closed bundle ring around the nodal flanks from smaller bundles which depart from the lateral branches of the complex leaf traces.
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12.
Zusammenfassung Hydrogenomonas facilis verwertet Thymin, Cytosin und Uracil als N-Quelle, Hydrogenomonas H 16 dagegen nur Cytosin. Durch Hydrogenomonas facilis wird Cytosin vollständig abgebaut, durch Hydrogenomonas H 16 lediglich desaminiert, wobei das entstehende Uracil in der Nährlösung angehäuft wird.In zellfreien Extrakten aus Hydrogenomonas H 16, die mit Cytosin als einziger N-Quelle gewachsen waren, wurde Cytosindesaminase-Aktivität im gekoppelten enzymatischen Test nachgewiesen, wobei Glutaminsäuredehydrogenase als Hilfsenzym diente. Mit Ammoniumchlorid herangezogene Zellen zeigten während der Indubation in Cytosin-haltigem Medium einen 18fachen Anstieg der spezifischen Cytosindesaminase-Aktivität.
Utilisation of cytosine and uracil by Hydrogenomonas facilis and Hydrogenomonas H 16
Summary Hydrogenomonas facilis utilizes thymine, cytosine, and uracil as nitrogen sources; Hydrogenomonas H 16, however, only cytosine. Cytosine is completely metabolised by Hydrogenomonas facilis, but is only deaminated by Hydrogenomonas H 16 and the resulting uracil accumulates in the culture medium.Cytosine deaminase activity was demonstrated in cell-free preparations from Hydrogenomonas H 16 which had been grown with cytosine as the sole nitrogen source. Enzyme activity was measured using a coupled enzyme assay in which glutamic acid dehydrogenase served as an accesory enzyme. An 18-fold increase in cytosine deaminase activity was observed in ammonia-grown cells during the incubation in a cytosine containing medium.
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13.
Systematics and distribution pattern of the free living nematodes in the benthos of Neusiedlersee outside the reed belt are described. 26 species have been found some of which demonstrate a distinct horizontal distribution pattern, correlated with the wind influence on benthic conditions in the lake. Detailed systematic account is given of the species found, especially the genera Udonchus Cobb and Monhystrella Cobb, as well as of the following species: Plectus andrassy Timm 1971, Paraphanolaimus microstomus (Daday, 1905), Monhystera spp., Theristus flevensis Schuurmans-Stekhoven, 1935, Tripyla glomerans Bastian 1865, Tobrilus gracilis (Bastian, 1865) and Amphidelus lemani longicaudatus n. ssp.
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14.
Different members of the Angiosperm familiesOleaceae, Scrophulariaceae, Plantaginaceae andAsteraceae with variable modes of pollination were studied in relation to ultrastructure of pollenkitt and exine. In entomophilous representatives the mostly electron-dense and homogeneous pollenkitt is located on the outside layer of the exine, making the pollen sticky. In related anemophilous taxa the pollenkitt mostly is electrontransparent and inhomogeneous; it becomes inactive by remaining in the loculus or sinking to the bottom of the exine caves; this makes the pollen powdery. According to such criteria,Fraxinus ornus andRhinanthus serotinus are entomophilous, whileFraxinus excelsior is anemophilous. The pollen ofLathraea squamaria eventually becomes powdery and suited for wind dispersal. The broad transition field between entomo- and anemophily is demonstrated byPlantago andArtemisia. Plantago lanceolata is anemophilous, whilePl. serpentina andPl. media are amphiphilous.Artemisia nitida andA. mutellina are entomophilous,A. absinthium, A. pedemontana andA. gabriellae are amphiphilous, but tend towards entomo- (A. absinthium) or anemophily (A. gabriellae), whileA. chamaemelifolia and especiallyA. vulgaris are anemophilous.
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15.
Zusammenfassung Vergleichende Untersuchungen über die Wirkung eines Carbamatherbizids und von Colchicin auf die Mitose von teilungsaktiven Wurzelspitzenzellen von Hordeum und Allium ergaben, daß die großen Unterschiede in der Empfindlichkeit zwischen Hordeum und Allium gegen das Carbamat in bezug auf das Spindelgift Colchicin nicht vorliegen, im Gegenteil, Hordeum ist weniger empfindlich als Allium.Colchicin wirkt vorzugsweise auf die Spindel und führt über C-Mitosen zur Polyploidie. Das Carbamat übt neben dem Einfluß auf die Spindel einen starken Effekt auf die Chromosomen aus, indem es zu Verklebungen und Zusammenballungen führt.
Investigations on the effects of a carbamate herbicide and of colchicine on mitosis of Allium cepa and Hordeum vulgare
Summary The marked differences in sensitivity of mitotically active root tip cells of Hordeum and Allium observed in response to a carbamate herbicide are not found in response to treatment with the spindle poison colchicine. Hordeum was less sensitive than Allium. Colchicine inhibited the spindle and caused c-mitoses and polyploidy. The carbamate herbicide inhibited the spindle and strongly affected the chromosomes; arrest of mitosis was primarily caused by stickiness and pycnosis of the chromosomes, spindle inhibition was of secondary importance.
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16.
Ohne Zusammenfassung
An analysis of the development of plastids and of the chloroplast pigments ofOenothera II. MutatedBiennis-plastids
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17.
Zusammenfassung Als weiterer Beweis für die Transformierbarkeit von Agrobacterium tumefaciens und Rhizobium leguminosarum werden wechselseitige Transformationsversuche durchgeführt und dabei die Resistenz gegen Streptomycin bzw. gegen ein Sulfonamid (Marbadal) als Selektionsmaterial benutzt. Die ermittelten Transformationsraten liegen in der Größenordnung von 4–7 · 10-6 bzw. 13 bis 16 · 10-6.
Interspecific transformations of Agrobacterium tumefaciens and Rhizobium leguminosarum
Summary As further proof for the transformability of Agrobacterium tumefaciens and Rhizobium leguminosarum reciprocal transformation assays were performed using the resistence against streptomycin resp. against a sulfonamide (Marbadal) as selection marker. The transformations rates are 4–7×10-6 resp. 13–16×10-6.
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18.
Cynoglossopsis somaliensis H. Riedl, sp. nov., is described as a new species of the hitherto monotypic genusCynoglossopsis Brand which is closest related toCynoglossum L. but has to be included inBoraginoideae-Eritrichieae from the way the nutlets are attached to the gynobasis.
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19.
Within agaric fungi whorled (multiple) clamps have been described so far only for the homothallicCoprinus myceliocephalus Lange. The new speciesCoprinus verticillatus Schulz-Weddigen (ined.) develops fertile mycelia which form septae without or with 1–5 clamps. Stronger hyphae tend to branch dichotomously. Most cells of the vegetative system contain many nuclei. Though single spore cultures remain sterile, they can develop multiple clamps, too. Moreover, very young mycelia produce a special type of oidiophores. According to its mating interactions a bipolar pattern characterizes the heterothallicC. verticillatus.
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20.
This paper deals with a filamentousCyanophycea from aSphagnum bog whose position in the current system is dubious. A characteristic feature, among others, is a certain rhythm of cell division and bipartition of the filaments. As a consequence, only 8-, 16- and 32-celled filaments are present in the population. An occasional disturbance of the rhythm is transitory. In the longitudinal direction the filaments exhibit mirror symmetry in regard to their middle.
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