bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unterschiede im Prolinstoffwechsel eines Peptidalkaloide‐produzierenden und eines nichtproduzierenden Stammes von Claviceps purpurea
Authors: Schlee D. , Böhmer Sylvia‐Annette 
Published: July 2010

AbstractTwo strains (pepty 695 and pur 221) of Claviceps purpurea have been used to study the dependence of proline turnover on incubation time (1, 3, 6, and 12 hours) under different culture conditions (synthetic saccharose‐citrate medium NL 720 and complex wort medium M 107) by means of tracer technique.In the saprophytically ergotoxine producing strain pepty 695 the proline is utilized in the protein and alkaloid biosyntheses. On the other hand, under non‐producing conditions (M 10) the radioactivity of proline‐14C is incorporated into many fractions and finally into CO2. In submerged culture (NL 720) the Claviceps strain pur 221 which does not produce ergolines uses proline only to a small extent in the protein biosynthesis, while most of this amino acid is not metabolized.The extent of uptake of proline is not correlated with the alkaloid synthesis.For comparison the turnover of l‐glutamate‐14C and d, l‐ornithine‐1‐14C by strain pepty 695 cultivated in the NL 720 medium has been studied.
Spaltung von Lactulose durch Bacillus megaterium
Authors: Leuchtenberger A. , Ruttloff H. 
Published: July 2010

AbstractIm Verlauf der Entwicklung eines Verfahrens zur Gewinnung einer neutralen Protease wurde ein Komplexmedium gefunden, in dem der verwendete Stamm Bacillus megaterium eine hohe Enzymaktivität ausschüttet. Untersuchungen über den Umsatz der eingesetzten Kohlenhydrate während der Fermentation zeigten, daß die als C‐Quelle verwendete Lactose bei der Sterilisation des Nährmediums partiell in Lactulose überführt wird. Dieses fructosehaltige Disaccharid wird vom Produktionsstamm rasch umgesetzt. Es wird der Nachweis erbracht, daß die im Zellinneren lokalisierte β‐Galaktosidase die glykosidische Bindung der Lactulose angreift. Die Spaltungsrate ist etwa gleich hoch wie diejenige bei Einsatz von Lactose.
Elektronenmikroskopische Beobachtungen zur Insertion der Pili bei dem neuisolierten Wasserstoff‐oxidierenden Bakterium 2K1
Authors: Mayer F. 
Published: July 2010

AbstractCells of the hydrogen‐oxidizing bacterium 2K1 exhibited numerous pili of varying length, with a diameter of 7–8 nm as measured from negatively stained samples. At the basis of each pilus, a cell wall differentiation was observed appearing, in face‐on view, as a ring‐like structure made up of subunits, and in side‐on view as a hollow cylinder penetrating through the cell wall. It is assumed that these ring‐like structures are in direct reation with the presence of the pili. As the number of ring‐like structures per cell was higher than the number of pili per cell, rings without associated pili might either be sites of polymerizing pili, or “dead” pilus channel complexes out of function due to pilus break‐down.
Glucoamylase aus Endomycopsis bispora I. Zur Produktion des Enzyms in Schüttelkultur
Authors: Ruttloff H. , Täufel A. , Zickler F. 
Published: July 2010

AbstractEin Stamm der Gattung Endomycopsis liefert unter geeigneten Kultivationsbedingungen Glucoamylase in hoher Ausbeute. Er läßt sich nach dem System von LODDER und KREGER VAN RIJ der Art Endomycopsis bispora zuordnen. Von den verschiedenen morphologischen Zustandsformen, in denen der Stamm auftritt, vermag nur die fädige Hyphenform hohe Enzymmengen zu produzieren. Es werden verschiedene C‐ und N‐Quellen sowie Phosphate hinsichtlich einer ausbeutesteigernden Wirkung getestet. Als besonders günstig erweisen sich hierbei Stärke, Maisquellwasser und organisch gebundenes Phosphat. Eine ökonomisch verwertbare Enzymbiosynthese beginnt erst am Ende der logarithmischen Wachstumsphase. Zu diesem Zeitpunkt sind Stärke wie auch Glucose bereits weitgehend verstoffwechselt. Die unter Einsatz dieser beiden Kohlenhydrate ermittelten Befunde sprechen dafür, daß die Enzymsynthese durch Glucose katabolisch reprimiert wird.
Einfluß alternierender Störungen auf die Verbrauchskennziffern beim Wachstum von Mikroorganismen
Authors: Heinritz B. , Bley T. 
Published: July 2010

AbstractIn technical microbiology microorganisms often undergo alternating milieu changes. For instance, this is the case in recirculation reactors. The organisms react on these changes with an increase of entropy production and in connection with this with increasing substrate consumption. This increasing substrate consumption contradicts the aim of an optimum yield from a given substrate. Thus, studies of the reaction of microbial growth to alternating milieu changes are of great importance.A simple model of the influence of alternating milieu changes on specific substrate consumption is given. In it the biological conversion of substances is built up by an irreversible consecutive reaction.After preliminary examinations on the analogue computer the reaction of the model to alternating perturbations is simulated on the digital computer. The results of the simulations are compared with experimental data.The good agreement of experiment and model justifies the use of the simple formulation in the preparation of technical processes.
Kinetic properties of the purified 3‐hexulosephosphate synthase from Pseudomonas oleovorans
Authors: Müller R. , Sokolov A. P. 
Published: July 2010

AbstractThe kinetic characteristics of the purified 3‐hexulosephosphate synthase from the facultative methylotroph Pseudomonas oleovorans were investigated. It could be demonstrated that the dependence of the reaction rate on the rib(ul)ose‐5‐phosphate as well as the formaldehyde concentration has a complex shape with the appearence of plateau and trough regions. The shape of the curve is changed in dependence on the fixed level of the second substrate.Multiple forms of the 3‐hexulosephosphate synthase were found to be responsible for the generation of the complex kinetic characteristics. By means of ion exchange chromatography it was possible to separate four active enzyme forms with different kinetic characteristics. These forms were also found to be interconvertible. This behaviour of the 3‐hexulosephosphate synthase is assumed to have the main regulatory function of the enzyme.
Glucoamylase aus Endomycopsis bispora. III. Morphologie‐abhängige Ausschüttung des Enzyms
Authors: Ruttloff H. , Winkler K. , Zickler F. 
Published: July 2010

AbstractEs werden die im Kulturmedium zu erhaltenden Enzymaktivitäten bei Vorliegen morphologsich reiner Formen von E. bispora (Hyphenform, Hefeform) ermittelt. Durch die Vorinkubation in einem Maisquellwasser‐medium wird in den Hyphenzellen ein System der Glucoamylasesynthese induziert, während es im synthetischen Medium nicht zur Induktion und zu einer nur geringen, oft an der unteren analytischen Nachweisgrenze liegenden Enzymausschüttung kommt. Die Ergebnisse von Untersuchungen zur Enzymausschüttung in Gegenwart oder bei Abwesenheit von Glucose weisen aus, daß die Glucoamylasesynthese von E. bispora ein induzierbares, katabolisch reprimierbares und von der morphologischen Form des Organismus abhängiges System ist. Da der Übergang von der Mycel‐ in die Sproßform mit einem sofortigen Abfall der Glucoamylaseausschüttung verbunden ist, stellt die Erhaltung der Hyphenform unter praktischen Bedingungen der Enzymgewinnung eine wichtige Vorbedingung für die Erzielung hoher Enzymausbeuten dar.
Substructural studies on sporulation of Saccharomycopsis lipolytica
Authors: Weber H. , Franzl E. 
Published: July 2010

AbstractDuring sporulation of diploids from crosses between different strains of the yeast Saccharomycopsis (Candida) lipolytica irregular numbers of ascospores per ascus have been observed. Using the serial section method it could be shown now by means of electron microscopy that in one‐, two‐, and three‐spored asci unenclosed “naked” nuclei occur additionally to nuclei incorporated in mature spores. It was demonstrated that the production of less than four spores per ascus in this yeast is not the result of a lack of meiotic products but of the nonutilization of nuclei could be demonstrated which indicate a normal meiotic division. All ascospores derived from asci with different spore numbers are uninuclear. It is assumed that a defect in spore formation caused by structural changes of chromosomes or aneuploidy should give rise to the occurrence of non incorporated nuclei and spore irregularity. It was concluded that meiosis and spore formation in Saccharomycopsis lipolytica seem to represent parallel and coordinated processes which generally resemble those recorded for Saccharomyces cerevisiae and Hansenula species.
Glucoamylase aus Endomycopsis bispora. V. Beeinflussung des Enzymbildungsvermögens durch Fette
Authors: Täufel A. , Winkler K. , Zickler F. , Ruttloff H. 
Published: July 2010

AbstractEs werden Untersuchungen zum Einfluß von pflanzlichen, tierischen und mineralischen Fetten sowie von speziellen Phosphatidfraktionen des Maisquellwassers auf die Glucoamylaseausschüttung durchgeführt. Hierbei zeigt sich, daß pflanzliche Öle (Rapsöl, Maiskeimöl, Reisöl) die Glucoamylasesynthese stimulieren, wobei die hierdurch erzielbare Ausbeutesteigerung vor allem durch die Anwesenheit von Maisquellwasser im Medium verstärkt wird. Bestimmte phosphatidreiche Franktionen des Maisquellwassers erhöhen die Biosyntheseleistung des Enzymproduzenten erheblich. Der oxydative Zustand des Öles beeinflußt die Glucoamylaseausschüttung. Bei Ölen mit geringer Peroxidzahl sind die Steigerungsraten deutlich erniedrigt.
Unterschiedliche Zusammensetzung der Zellwand‐Polysaccharide beiSaccharomyces cerevisiae S288 und einer osmolabilen Mutante
Authors: Reuter G. , Märkisch U. , Hering V. , Venkov P. V. 
Published: July 2010

AbstractDetermination of the polysaccharide contents and structural studies on the mannan by acetolysis and permethylation analysis shows an altered polysaccharide biosynthesis of the osmoticsensitive mutant VY 1160 of Saccharomyces cerevisiae S 288. The mutant contains more glucan, less mannan, and less alkali‐soluble glycogen. Its mannan is characterized by more short side chains and less long side chains. Its main chain is 1 → 6‐linked, but its side chains consist of more 1 → 3‐ than 1 → 2‐linked mannose units.
Dynamics of anerobic growth of Saccharomyces cerevisiae in the chemostat
Authors: Wòjcik M. , Wieluński J. 
Published: July 2010

AbstractA kinetic MONOD model has been used to describe the dynamic response of a continuous stirred tank fermentor (CSTF) to changes in dilution rate. A general analytical solution of a lineraized model was obtained. Experimental results (VAIRO et al. 1977) of continuous anaerobic culture of Saccharomyces cerevisiae have verified the model quantitatively. For step disturbances on the dilution rate the responses of biomass concentration and the outlet substrate concentration were calculated on a digital computer and compared with the experimental data.
Distribution functions of variables characterizing the mycelial morphology of Streptomyces hygtroscopicus grown in glucose‐limited chemostat cultures
Authors: Riesenberg D. , Erdmann A. , Bergter F. 
Published: July 2010

AbstractThe distribution of variables characterizing the morphology of the mycelium of Streptomyces hygroscopicus grown in glucose‐limited chemostat cultures at different specific growth rates were investigated statistically. The values of the hyphal growth unit (L/N) and the values of the distance from the apex to the first branch (Lp) are normally distributed, but the values of the distance between neighbouring branches are logarithmically normal distributed. The distribution functions are discussed from the biological point of view.
Studies on the substrate specificity of the DNA methylase activity from Escherichia coli K‐12
Authors: Schmidt A. , Reinert H. , Venner H. , Bieber J. 
Published: July 2010

AbstractA partially purified extract of DNA methylases from E. coli K‐12 containing DNA‐adenine as well as DNA‐cytosine methylase activities has been examined with respect to different DNA species as substrates. The results show that the natural content of 6‐MAP1) in the applied DNA represses the DNA‐adenine methylase activity. On the other hand, 5‐MC, already present in the substrate does not influence the activity of the DNA‐cytosine methylase. DNA from Micrococcus radiodurans, which is completely free of methylated bases served as comparison.Since netropsin preferentially binds to AT‐rich regions of DNA, the influence of this oligopeptide antibiotic on the methylation of DNA was investigated. As expected the antibiotic predominantly inhibits adenine methylation of DNA. The degree of inhibition depends on the molar ratio of netropsin to DNA phosphate.
Studies of colicin action on wall‐less stable L‐forms of Escherichia coli I. Degree of attachment and of killing effect on rods and stable L‐form cells
Authors: Šmarda J. , Schuhmann Edith 
Published: July 2010

AbstractEscherichia coli strains B and K12 W 1655 F+ are able to bind more lethal units of colicins E2, E3, G, H, Ia, and K + X per one stable L‐form cell (of the protoplast type) than per one rod cell; colicin D is bound in a higher amount on E. coli B rods. This pattern remains unchanged, if the same colicins are attached on chloroform‐killed cells of both forms. Rods of both E. coli strains are more sensitive to colicins D, E2, E3, K + X (as – in the strain B – to colicin Ia) than cells of the respective L‐forms. In the strain W 1655 F+ both cell forms are equally highly sensitive to colicin Ia. The stable L‐forms of both strains are much more sensitive to colicins G and H than the rods.Thus the Gram‐negative cell wall decreases the probability of a colicin molecule to get attached to its receptor in the cytoplasmic membrane. On the other hand, in E. coli cells the attachment of most colicin molecules to the wall receptors increases the probability of their biological effect. There is no such effect of the wall‐attachment on the action of colicins G or H.The strain B is tolerant to colicin E2, while being resistant to E3; thus the cytoplasmic membrane receptor sites for them are not identical.
Glucoamylase aus Endomycopsis bispora IV. Ausscheidung multipler Formen im Verlaufe der Kultivation
Authors: Winkler K. , Ruttloff H. , Zickler F. 
Published: July 2010

AbstractIn den von E. bispora gebildeten Glucoamylasespektren werden insgesamt 10 Isoenzyme nachgewiesen, die unterschiedlich stark in das Medium ausgeschieden werden und in unterschiedlichem Grade einer Repression unterliegen. Die größten Veränderungen im Bandenmuster treten während der logarithmischen Wachstumsphase auf; während dieser Zeit erfolgt die Metabolisierung der C‐Quelle. Die mit α1 bezeichnete Bande unterliegt am stärksten einer katabolischen Repression, steuert aber unter Derepressionsbedingungen (stationäre Phase) den größten Anteil zur Gesamtaktivität bei. Für den hohen Anteil an multiplen Formen steht eine Erklärung noch aus. Infolge der nur sehr geringen Proteaseaktivität im Kulturfiltrat ist eine extrazellulär ablaufende limitierte Proteolyse von Glucoamylasekomponenten wenig wahrscheinlich.
Dielektrophorese als Grundlage für ein neues Verfahren zur präparativen Zelltrennung
Authors: Glaser R. , Pescheck Ch. , Krause G. , Schmidt K. P. , Teuscher L. 
Published: July 2010

AbstractDielektrophorese ist die Bewegung polarisierbarer Teilchen in einem inhomogenen elektrischen Wechselfeld in Richtung steigender Feldstärke. Entsprechend der Polarisierbarkeit der Partikeln ist dieser Effekt frequenzabhängig. Es wird eine präparative Trennkammer beschrieben, die auf folgendem Prinzip beruht: In einem Elektrodenraum sammeln sich Zellen durch den Dielektrophorese‐effekt an einer koaxial gelegenen Drahtelektrode. Dieser Draht wird mit konstanter Geschwindigkeit bewegt, so daß die angehefteten Zellen kontinuierlich in eine vom Feld abgeschirmte Spülkammer überführt werden. Hier lösen sie sich vom Draht und gehen in Suspension. Der Trenn‐effekt wird an lebenden und toten Zellen von Saccharomyces cerevisiae sowie an zwei Arten von Oscillatoria demonstriert. Die Trennmethode spricht auf zellphysiologische Differenzen an und ist besonders für solche Zellen geeignet, die Suspensionslösungen geringen Salzgehaltes tolerieren.
Nutzung von Gen5 und Gen6 ts‐Mutanten des Phagen T3 für die Anzeige von Hemmstoffen der DNS‐Synthese
Authors: Scholz D. , Meissner Ch. , Rosenthal H. A. 
Published: July 2010

AbstractIn an enzyme‐specific drug screening system nalidixic acid and 3'FTdR, inhibitors of DNA synthesis, both reduce the growth of wild type and temperature‐sensitive point mutants of phage T3 with different efficiencies. The wild type shows the strongest sensitivity against the drugs, while an exonuclease mutant is the most insensitive variant. The DNA polymerase mutants exhibit an intermediate degree of inhibition.The anthracycline antibiotics violamycin BI and adriblastin which preferentially inhibit RNA synthesis show the same degree of inhibition for all mutants. This is true also for the RNA synthesis inhibitor lambdamycin, which is identical with chartreusin. The protein synthesis inhibitors chloramphenicol and o‐phenanthroline, a chelating agent, impair all mutants to the same extent.Our data confirm the hypothesis that structural variants of essential viral enzymes, when compared with the wild type should sensitivities against specific inhibitors and show that this T3 system could be used for the indication of specific inhibitors of DNA synthesis.
Eigenschaften der Rubredoxin‐Reductase aus dem alkanassimilierenden Bakterienstamm Acinetobacter calcoaceticus
Authors: Claus R. , Asperger O. , Kleber H.‐P. 
Published: July 2010

AbstractIn Acinetobacter calcoaceticus läßt sich nach Wachstum auf langkettigen n‐Alkanen eine Rubredoxin‐Reductase nachweisen, welche spezifisch den Elektronentransport von NADH über Rubredoxin – nicht aber über Ferredoxin oder Adrenodoxin – zum Cytochrom c katalysiert. Die Cytochrom c‐Reduktion der etwa 30fach angereicherten Rubredoxin‐Reductase ist der eingesetzten Rubredoxin‐Reductase‐Konzentration und Rubredoxinmenge proportional. Neben Dichlorphenolindophenol (Km = 2,5 × 10−6 mol/l) is Hexacyanoferrat (Km = 5,5 × 10−6 mol/l) ein wirksamer Elektronenakzeptor. Der Km‐Wert für NADH wurde in Cytochrom c‐Reduktionstest als auch mit Hexacyanoferrat als Elektronenakzeptor einheitlich mit 1,1 × 10−4 mol/l bestimmt.Das pH‐Optimum der Rubredoxin‐Reductase liegt bei pH 7,7 (0,01 mol/l Phosphatpuffer) bzw. 8,5 (0,05 mol/l Tris/HCl‐Puffer). Die Reaktionsgeschwindigkeit der Cytochrom c‐Reduktion wird durch Erhöhung der Molarität des Phosphatpuffers vermindert. Zusatz von FAD – nicht aber von FMN – steigert die Reductaseaktivität. FAD scheint die prosthetische Gruppe der Rubredoxin‐Reductase zu sein.Der Einfluß verschiedener Verbindungen (Ionen, SH‐Reagenzien, Hemmstoffe der Atmungskette u. a.) auf die diaphoretische Aktivität und die Cytochrom c‐Reduktion wird untersucht.
Steroidumwandelnde Enzyme aus Mikroorganismen XI. Reversibilität der Dehydrierungsreaktion der Steroid‐1‐Dehydrogenase aus Nocardia opaca
Authors: Groh H. , Komel R. , Deppmeyer V. , Atrat P. , Hörhold C. 
Published: July 2010

AbstractHighly purified preparations of the 4‐en‐3‐oxosteroid: (acceptor)‐1‐en‐oxidoreductase from Nocardia opaca have been investigated in both types of reactions: 1.2‐dehydrogenation of the 4‐en‐3‐oxo‐derivative and 1.2‐hydrogenation of the 1.4‐dien‐3‐oxo‐derivative. It was not possible to separate the hydrogenating activity from the dehydrogenating activity by affinity chromatography, disc electrophoresis, SDS‐electrophoresis, and isoelectric focusing techniques. The pure enzyme preparation is discussed as only one FAD depending protein acting in response to the system as a dehydrogenase as well as a reductase.
Nitrate respiration of Klebsiella pneumoniae on amino acids, especially on serine
Authors: Kikuchi S. , Ishimoto M. 
Published: July 2010

AbstractAnaerobic growth on an amino acids mixture in the presence of nitrate of a strain of K. pneumoniae isolated from soil depended on the presence of serine in the mixture. This organism grew on serine as sole carbon source under anaerobic conditions in the presence of nitrate but not in its absence. Glycylglycine could replace serine. Serine was degraded to acetate, formate, pyruvate, acetone and acetoin with formation of nitrite under these conditions. These products were practically not different from those formed from glucose. Resting cells decomposed serine also in the absence of nitrate forming butanediol and a large amount of formate in place of decreased amounts of acetate and pyruvate. These cells also anaerobically decomposed alanine to products similar to those from serine and phenylalanine to phenylacetate and formate only in the presence of nitrate. Valine was not catabolized under the same conditions. Serine was decomposed to pyruvate and ammonia in the crude extract in the presence and absence of nitrate, indicating participation of serine dehydratase in its breakdown. Phenylalanine appears to be decomposed to phenylpyruvate by transamination coupled to glutamate oxidation and then to phenylacetate and formate. Little growth on serine under anaerobic conditions in the absence of nitrate may be accounted for by the small gain of ATP in the anaerobic breakdown of serine by this organism.
Light microscopic investigations on lysozyme‐ and penicillin‐induced morphological changes in Erysipelothrix rhusiopathiae and on propagation of its protoplast type L‐form
Authors: Gumpert J. , Todorov T. , Toshkov As 
Published: July 2010

AbstractAlthough lysozyme and penicillin are different in their molecular action on cell wall murein they produce similar morphological changes in Erysipelothrix rhusiopathiae grown on agar media. 2,000–5,000 μg/ml lysozyme and 0.1–1 IU/ml penicillin induce filament formation. Filaments are able to divide in rods, which shows that only cross wall formation and separation are inhibited. Higher doses of lysozyme (10,000 μg/ml) and penicillin (>1 IU/ml) inhibit cell wall synthesis and induce L‐form growth. The propagation of this protoplast type L‐form was investigated by microphotographic series in phase contrast microscope during L‐form induction and in the stable L‐form state. In both cases L‐form cells propagate by formation and growth of small granular elements of about 0.2–0.6 μm in diameter, which spread in different directions in the agar medium. The multiplication process may be explained by the plasticity and flexibility of the L‐form cell and its cytoplasmic membrane and by the structural and functional interaction between the “folded chromosome” and the surrounding cytoplasm.
Effect of certain herbicides on survival, growth, and nitrogen fixation of blue‐green alga Anabaena doliolum Bharadwaja
Authors: Kapoor Kamal , Sharma V. K. 
Published: July 2010

AbstractGrowth and fixation of nitrogen were retarded in Anabaena doliolum when grown on elemental nitrogen in presence of four different herbicides. The alga was found to be intolerant to these chemicals under nitrogen fixing conditions even in low concentrations. An inhibition of photosynthesis has been regarded as the main basis of herbicidal activity besides other interactions.