bluuebunny/crossref_metadata_2025_split huggingface dataset:
Binding of a bacteriophage to wall‐membrane adhesion in Proteus mirabilis
Authors: Cole S. A. , Smith D. G. 
Published: July 2010

AbstractA bacteriophage was shown to adsorb to plasmolysed non‐swarming cells of Proteus mirabilis preferentially at the sites of adhesion between the inner membrane and outer cell wall membrane; 75% of phage particles were adsorbed at these sites, while 25% were not. Differences in outer membrane composition between swarming and non‐swarming cells were reflected in altered phage‐binding properties, with only 33% of phage absorbed at these adhesion sites in swarming cells. On the basis of their phage distribution, cross‐sections of swarm cells could be distinguished from sections of short non‐swarming cells.
Biotin deficiency in yeast: Electron microscopic analysis
Authors: Jirků V. , Ludvík J. , Čejková A. , Krumphanzl V. 
Published: July 2010

AbstractAn electron microscopic comparison was made of the cytological responses of Saccharomyces cerevisiae to growth factor deficiency. Ultrathin sections of exponential deficient cells revealed a thickening of cell wall and a conversion of central vacuole into a vacuolar system. Common alteration in cytology of deficiency stationary cells in condensed vacuolar material.
Cyanide‐resistant respiration in a respiration‐deficient mutant of Saccharomyces cerevisae
Authors: Arrabaça J. D. , Loureiro Dias M. C. 
Published: July 2010

AbstractA respiration‐deficient mutant of Saccharomyces cerevisiae, grown aerobically with glucose as the sole source of energy and carbon, showed residual respiration resistant to cyanide. The differential sensitivity of cell fractions to inhibition by hydroxamic acids and carbon monoxide suggested that more than one type of organelle, probably mitochondria and microsomes, was involved in the consumption of oxygen.
Preparation and characterization of proteases from Thermoactinomyces vulgaris V. Investigations on autolysis and thermostability of the purified protease
Authors: Behnke U. , Ruttloff H. , Kleine R. 
Published: July 2010

AbstractThermitase, the main component of the proteases of the culture medium from Thermactinomyces vulgaris, is degraded by autolyses (increase of liberated amino groups) and thereby inactivated especially at elevated temperature, at alkaline pH‐values and in the absence of added substrates. As shown by polyacrylamide gel electrophoresis autolysis is an essential part during heat inactivation (complete disappearance of the thermitase band after heating the enzyme at 85°C for 5 min). The quantitative comparison of autolysis and heat inactivation as well as the kinetics of reversible inhibition of the enzyme by HgCl2 at different temperatures showed that above 60°C thermal denaturation of the enzyme protein contributes to thermitase inactivation. Ca2+‐ions (20 mM) have a stabilizing effect against both autolysis and thermal denaturation (inactivation) of thermitase.
Einfluß von Nalidixinsäure auf die Aktivierung der RNA‐Synthesen auswachsender Sporen von Bacillus subtilis
Authors: Hecker M. 
Published: July 2010

AbstractOutgrowth of B. subtilis spores depends on the action of DNA gyrase (comp. MATSUDA and KAMEYAMA 1980). Application of nalidixic acid (100 μg/ml) to dormant spores of Bacillus subtilis prevents the outgrowth. Application of nalidixic acid (100 μg/ml) during the early outgrowth phase (after a 20 min germination period) does not prevent, but only delay spore outgrowth. Germination of spores is not influenced.Nalidixic acid is an effective inhibitor of RNA synthesis in outgrowing spores, whereas vegetative cells are more resistant. Spores cn grow out inspite of a remarkably reduced intensity of RNA synthesis.Nalidixic acid particularly inhibits the synthesis of stable RNA, probably that of ribosomal RNA.We suggest that DNA gyrase‐catalyzed alterations in DNA structure are involved in the regulation of the gene expressional program of outgrowing B. subtilis spores.
Abbau von Mischsubstraten durch Hefen I. Substrate der Sulfitablauge
Authors: Krauel Ute , Krauel H. H. , Weide H. 
Published: July 2010

AbstractTwo Candida strains were isolated from an industrial batch reactor for fermentation of waste sulfite liquor.Pure cultures of these yeasts assimilate single substrates contained in waste sulfite liquor with different specific activity. The respiration rate is influenced by some induction substrates, too.In a mixed substrate model corresponding to waste sulfite liquor the single substrates are metabolized by pure cultures in a specific sequential manner.These sequences change during degradation of mixed substrates by mixed cultures. The spectrum of metabolized substrates, however, is not reduced. This fact is important for energy balance or for waste water contamination.
Genetic segregation in a high‐yielding streptomycin‐producing strain of Streptomyces griseus
Authors: Roth M. , Schwalenberg B. , Reiche R. , Noack D. , Geuther R. , Eritt I. 
Published: July 2010

AbstractThe streptomycin‐producing Streptomyces griseus HP spontaneously segregated non‐reverting derivatives with altered phenotypes. Clones characterized by increased spore formation and decreased streptomycin production were found. Two other types of derivatives were defective in aerial mycelium and streptomycin formation as well, but differed in the capacity to synthesize a yellow pigment. These derivatives were examined with respect to further properties.The stability of S. griseus HP was investigated in relation to conditions of continuous culture. Both at 26 and 30°C, under glycerol and NH4Cl limitation a rapid segregation and enrichment of streptomycin‐non‐producing derivatives occurred. At 34°C and glycerol limitation segregation began only after about 35 generations of continuous culture. In NH4Cl‐limited chemostats the original strain was stable during 80 generations. In the course of the continuous culture experiments it was shown that the onset of genetic segregation with mycelia can be detected before it becomes obvious in colonies grown from the mycelia. This was achieved by fractionation of the mycelia by protoplast formation and subsequent plating on regeneration medium allowing colony growth and differentation.
Effects of freezing and thawing and storage by freezing on the biological and morphological properties of strain K‐9 of Klebsiella pneumoniae and its variants
Authors: Takahashi M. , Ito S. , Yoshida K. 
Published: July 2010

AbstractUsing strain K‐9 of Klebsiella pneumoniae and its variants A, B and C, which possess a large, small, or extra‐small capsule or are unencapsulated, and exhibit high, middle, or low mouse virulence or avirulence in the mouse, respectively, the effect of freezing and thawing on the protection and storage by freezing in 20% skim milk solution on their biological and morphological against freezing and thawing in the order variant C, the parent strain, variants A and B. 20% skim milk solution was the most favourable for survival of the organisms compared to trypticase soy broth and 10% glycerol. Their mouse virulence was similarly sensitive to freezing and thawing experiments although no alteration of their biochemical properties was observed. When the organisms were suspended in 20% skim milk solution and stored for 2 years at –70°C, their mouse virulence was not altered. When morphological features were tested electron microscopically, cellular injuries such as vacuola or fissions of cell walls were observed in the variants but not in the parent strain. However, it was evident that conversion to unencapsulation from capsulation occurred at a high frequency in the parent strain and in variant A when determined by the colonial morphologies in soft‐agar medium.
In vitro‐Einbau von 14C‐Hexose‐6‐phosphat in Mannan, β‐Glucan und Glycogen bei Candida spec. H und ihren Mutanten
Authors: Röber B. , Reuter G. 
Published: July 2010

AbstractMannose‐6‐p is an activator of the 14C‐mannose incorporation from GDP‐14C‐mannose in the mono‐ and oligosaccharides and in the mannopolymers of the cell wall proteophosphomannan produced by the food protein yeast Candida spec. H.Moreover, mannose‐6‐p is a precursor of proteophosphomannan: 14C‐Mannose‐6‐p has been incorporated in absense of GTP. Corresponding behaviour shows glucose‐6‐p by synthesis of β‐glucan and glycogen. Mutants of Candida spec. H with different efficiency in the biosynthesis of mannan, β‐glucan and glycogen incorporate hexose‐6‐p in a different extent.
Yield coefficients in dependence on milieu conditions and cell states III. Induction of synchrony in continuous yeast cell cultivation by milieu changes
Authors: Stichel E. , Rogge G. , Bley T. , Heinritz B. 
Published: July 2010

AbstractInduction of synchrony by various perturbations in continuous yeast cultivation on hydrocarbons of crude oil is described. Short‐time temperature and pH‐value shocks cause oscillations of budding cell percentage in the order of the cell cycle duration. An abrupt change of the phosphate ion concentration of the nutritional medium may also induce a synchronization of microbial growth. However, the frequency corresponds with the eigenfrequency of the fermentation process. The experimental values were investigated statistically using autocorrelation and spectral analysis.
Steroidumwandlung mit immobilisierten Mikroorganismen
Authors: Atrat P. 
Published: July 2010

AbstractThe application of immobilized microbial cells has been receiving increasing interest, in particular because of their potential for use in industrial fermentation processes and in analytical procedures. Since the first application of an immobilized microbial biocatalyst for steroid transformation in 1970 by MOSBACH and LARSSON many results have been published concerning the use of such type of biocatalyst in steroid biochemistry and steroid microbiology, respectively. The review deals with the present scientific state of the steroid transformations performed with immobilized biocatalysts, their applications and development trends. In particularly the following aspects are discussed: 1(2)‐dehydrogenation or hydrogenation, hydroxylation reactions, redox processes in 3,17‐ and 20‐oxogroups, side chain splitting of sterols, 5α‐reduction, modification of cholic acid derivatives and the use of immobilized plant cells. The possibility for application of microbial membrane electrodes in steroid analysis has been shown. Up to now, many results of fundamental research are known. There are possibilities for producing expensive steroid derivatives in laboratory apparatures using immobilized biocatalysts. Some of the processes, described here, are of practical interest, and some of them are said to be used industrially, respectively.
Gemeinsame Verwertung von Glucose und n‐Alkanen bei der Citronensäuresynthese durch Saccharomycopsis lipolytica
Authors: Franke‐Rinker D. , Behrens U. , Nöckel E. , Forner Ch. , Portnowa A. 
Published: July 2010

AbstractFermentations for the overproduction of citrate and isocitrate with S. lipolytica in media containing both glucose and n‐alkanes as mixed C‐source have been performed. Biomass and product yields strongly depend on the C‐source of the inoculation culture. If the inoculation culture had been taken from media containing glucose as sole C‐source both glucose and n‐alkanes were utilized for cell growth in the main culture whereas only glucose was utilized if the inoculation medium contained only n‐alkanes.For idiophasic citrate and isocitrate production both glucose and n‐alkanes were consumed independently of the C‐source of the inoculum but that C‐source was preferentially utilized which has been the C‐source of the inoculation culture.These findings are reflected by the activities of the isocitrate lyase and the pyruvate carboxylase, respectively. In S. lipolytica both anaplerotic pathways are coexisting but the C‐source of the inoculation culture determines the level of the specific activities even if the ratio of the cell‐mass of the inoculum to the cell‐mass of the main culture at the end of the growth phase is about 1:35.
Lytic enzyme activity in autolysing mycelium of Aspergillus niger
Authors: Lahoz R. , Reyes Fuensanta , Gómez P. , Martinez M. J. 
Published: July 2010

AbstractWe have studied changes in the activity of some lytic enzymes contained in mycelium of Aspergillus niger in cultures relative to the autolytic phase of growth. Acid phosphatase, polygalacturonidase and α‐amylase activity reached its highest level (40.7, and 8 U/sample, respectively) at the initiation of the autolytic phase of growth. 1,3‐ß‐Glucanase and ß‐N‐acetylglucosaminidase reached its highest level (3.5 and 2 U/sample, respectively) during the first days of autolysis.Alkaline phosphatase, cellulase, invertase, esterase, chitinase and proteolytic activity is also present in autolysing mycelium of A. niger, though comparatively low. Their maximum activity coincided with the beginning of the autolytic phase of growth. In all enzymes studied here, as autolysis proceeded, enzyme activity decreased by about 90%. Only esterase activity remained nearly constant throughout the whole period of autolysis described here.
Water‐borne fungi in the River Inn, Innsbruck (Austria)
Authors: El‐Sharouny H. M. , Tiefenbrunner F. 
Published: July 2010

AbstractPythium, Saprolegnia and Achlya were the basic components of the river mycoflora. Occurrence and periodicity of the fungal genera and species exhibited three different patterns during the different months of this investigation.
Regulation der Citratsynthase bei fakultativ methylotrophen Bakterien
Authors: Müller‐Kraft Gabriele , Babel W. 
Published: July 2010

AbstractCommonly the TCA cycle fulfils an anabolic and a catabolic function in case of aerobic chemo‐organoheterotrophic nutrition. In methylotrophic growth the TCA cycle is dispensable as a bioenergetic pathway. This is reflected by properties of citrate synthase in facultative methylotrophic bacteria. Two citrate synthases, a ‘chemoorganoheterotrophic’ one, which is inhibited by NADH (or ATP in Acetobacter MB 58), and a ‘methylotrophic’ one, which is not or less affected by energy indicators, were found in Pseudomonas oleovorans, Pseudomonas MS, Pseudomonas MA, and Acetobacter MB 58. The concentration of these citrate synthases depends on the manner of nutrition. Bacteria with ICL‐negative‐variant of the serine pathway and with ribulosebisphophate pathway seem to possess only a ‘chemoorganoheterotrophic’ citrate synthase. Possibly the anabolic function of this citrate synthase can be realized by metabolites.
Selection of yeasts for single cell protein production on media based on Jerusalem artichoke extracts
Authors: Apaire Véronique , Guiraud J. P. , Galzy P. 
Published: July 2010

AbstractSeveral yeast strains can grow with good yield (0.16 to 0.19 mg protein/mg carbohydrate) on nitrogen supplemented Jerusalem artichoke extract. The most promising strain is Lipomyces starkeyi. Including by‐products (pulps, proteins of extract), protein production can reach 2 metric tons/ha.
Degradation of aniline and monochloroanilines by Rhodococcus sp. An 117 and a pseudomonad: A comparative study
Authors: Kaminski U. , Janke D. , Prauser H. , Fritsche W. 
Published: July 2010

AbstractTwo newly isolated aniline‐degrading bacterial strains were characterized with regard to their enzyme systems responsible for aniline catabolism. One of them identified as a Rhodococcus sp. metabolized aniline exclusively via the β‐ketoadipate pathway by means of inducible enzymes. The aniline‐degrading enzyme system of the second isolate, presumably a pseudomonad, was shown to consist of an inducible aniline‐converting enzyme and constitutive meta‐pathway enzymes. Both isolates failed to metabolize monochlorinated anilines in the absence of additional carbon sources. To explain this the ring‐cleaving enzymes of both isolates were examined for their substrate specificities. Furthermore, the effect of 4‐chlorocatechol on the enzymes catalyzing aniline conversion and catechol oxygenation was investigated.
Formation of additional contacts of chromosome with membrane in the process of DNA repair synthesis in bacterial cells
Authors: Bezlepkin V. G. , Malinovsky Yu. Yu. , Gaziev A. I. 
Published: July 2010

AbstractAn increase in the amount of membrane‐bound DNA was found in B. subtilis cells with UV‐induced DNA repair synthesis as compared to untreated cells. It was shown that DNA repair synthesis occurred in DNA membrane complexes (DMC) formed during UV‐irradiation. UV‐induced formation of DMC was observed in cells of wild type strains which were capable of repairing damaged DNA but not in a mutant defective in DNA‐polymerase I. It was demonstrated that DNA‐polymerase I is located on the membrane of B. subtilis cells. This suggested a participation of DNA‐polymerase I in binding of the chromosome to the membrane in UV‐irradiated cells. UV‐induced DMC did not dissociate when the cells were treated with inhibitors of DNA‐gyrase. It, therefore, was qualitatively different from the DMC found during replication. The mechanisms of binding of the damaged DNA to the membrane in UV‐irradiated cells of B. subtilis are discussed.
Intracytoplasmic membrane induction by hexadecane in Acinetobacter calcoaceticus
Authors: Müller H. , Naumann A. , Kleber H.‐P. 
Published: July 2010

AbstractAcinetobacter calcoaceticus 69‐V is capable of utilizing n‐alkanes as the sole carbon source. By conventional and high voltage electron microscopy the fine‐structure of these bacteria grown on hexadecane (with or without addition of DL‐carnitine), succinate or yeast extract was analysed. A. calcoaceticus grown on hexadecane exhibited intracytoplasmic unit membrane aggregates in contrast to controls grown on the nonhydrocarbon substrates. Probably these aggregates are formed by the cytoplasmic membrane. Most of these membranes are surrounding and penetrating hexadecane inclusions. Ultrastructurally no essential difference caused by addition of carnitine could be seen. The results suggest that the membrane aggregates are the sites of enzymes which are required for the utilization of hexadecane.
Aufnahme und Oxidation von Monosacchariden bei Acinetobacter calcoaceticus
Authors: Kleber H.‐P. , Haferburg D. , Asperger O. , Schmidt M. , Aurich H. 
Published: July 2010

AbstractAcinetobacter calcoaceticus 69‐V is not able to grow on carbohydrates or its derivatives and to use them as sole carbon sources. On the other hand, the partial oxidation of several monosaccharides (glucose, galactose, mannose, xylose, arabinose, ribose) by intact cells has been demonstrated by acid production and measurements of oxygen consumption.Glucose and fructose are taken up by intact cells. Different transport systems exist for the uptake of both hexoses. The “apparent” KM‐values for the membrane transport amount to 1.5 · 10−3 and 1.7 · 10−4 moles/l for glucose and fructose, respectively. Gluconolacton only inhibits the transport of glucose, whereas the transport of both hexoses is inhibited by uranylacetate. Other monosaccharides and metabolic inhibitors are without effect. An exchange of intracellular against extracellular glucose has not been found.Gluconate and CO2 have been identified as extracellular products of glucose oxidation after an incubation period of more than 5 min, whereas gluconate and 6‐phosphogluconate have been detected as intracellular products. No oxidation products have been found using fructose as substrate.No activity of hexokinase, phosphofructokinase, pyruvate kinase, and 6‐phosphogluconate dehydrogenase have been detected in cell‐free extracts of sonicated cells. An aldose dehydrogenase coupled with an electron transport system occurs in the membrane fraction. The presence of this enzyme was demonstrated by the reduction of dichlorophenolindophenol as well as by oxygen consumption which is inhibited by cyanide.The aldose dehydrogenase exhibits a broad substrate specificity against different aldohexoses and aldopentoses differing by their KM‐values. Cytochrome b and the terminal oxidase cytochrome o are components of the electron transport system. Neither hydrogen peroxide is formed, nor pyridine nucleotides participate in aldose dehydrogenation.
Comparison of protein patterns of Streptomyces griseus spores from surface and submerged cultures
Authors: Valu G. , Vitális S. , Békési I. , Szabó G. 
Published: July 2010

AbstractProtein patterns of conidia produced by a Streptomyces griseus strain in submerged cultures and on solid media were compared. Cell‐free extracts (30000 X g supernatant) were prepared and analyzed on gradient SDS polyacrylamide gels. The protein patterns of both kinds of conidia were found to be practically identical, and they differed from protein patterns of the old vegetative hyphae in a characteristic way.
A new fluorimetric assay for streptothricins
Authors: Hesse G. , Römer W. , Miosga N. 
Published: July 2010

AbstractIn strongly acidic medium (70% HClO4) streptothricins form a fluorophore (λex = 312 nm; λem = 381 nm) with unknown structure. A fluorimetric determination of pure or crude products and cultures, respectively, was worked out based on this reaction. Concentrations for fluorescence measurements were in the range of 10−8 — 2 · 10−7 moles. Interferences of the assay are discussed, a statistical evaluation of results and a comparison between microbiological and fluorimetric findings are given.
Vimentin contributes to changes in chondrocyte stiffness in osteoarthritis
Authors: Haudenschild Dominik R. , Chen Jianfen , Pang Nina , Steklov Nikolai , Grogan Shawn P. , Lotz Martin K. , D'Lima Darryl D. 
Published: July 2010

AbstractActin and tubulin cytoskeletal components are studied extensively in chondrocytes, but less is known about vimentin intermediate filaments. In other cell types, vimentin is a determinant of cell stiffness and disruption of vimentin networks weakens the mechanical integrity of cells. Changes in vimentin organization correlate with osteoarthritis progression, but the functional consequences of these changes remain undetermined in chondrocytes. The objective of this study was to compare the contribution of vimentin to the mechanical stiffness of primary human chondrocytes isolated from normal versus osteoarthritic cartilage. Chondrocytes were embedded in alginate and vimentin networks disrupted with acrylamide. Constructs were imaged while subjected to 20% nominal strain on a confocal microscope stage, and the aspect ratios of approximately 1,900 cells were measured. Cytosolic stiffness was estimated with a finite element model, and live‐cell imaging of GFP‐vimentin was used to further analyze the nature of vimentin disruption. Vimentin in normal chondrocytes formed an inner cage‐like network that was substantially stiffer than the rest of the cytosol and contributed significantly to overall cellular stiffness. Disruption of vimentin reduced stiffness approximately 2.8‐fold in normal chondrocytes. In contrast, osteoarthritic chondrocytes were less stiff and less affected by vimentin disruption. This 3D experimental system revealed contributions of vimentin to chondrocyte stiffness previously not apparent, and correlated changes in vimentin‐based chondrocyte stiffness with osteoarthritis. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:20–25, 2011