bluuebunny/crossref_metadata_2025_split huggingface dataset:
Steroidtransformation mit immobilisierten Mikroorganismen. III. Abbau der Seitenkette von Cholesterolderivaten mit immobilisierten Zellen von Mycobacterium phlei und M. smegmatis
Authors: Atrat P. , Hörhold C. , Buchar M. J. , Koschtschejenko K. A. 
Published: July 2010

AbstractThe cholesterol derivatives 3,3‐ethylenedioxycholest‐5‐en I and 4‐cholesten‐3‐(0‐carboxymethyl)oxime II were transformed into the coresponding androstenedione derivatives by selective cleavage of the sterol side chain with immobilized preparations of Mycobacterium phlei IMET SG 1026 and M. smegmatis IMET H 124. The influence of three immobilization methods on fermentation activity and stability was investigated. The immobilized cells of M. phlei IMET SG 1026 were found to be suitable to transform the structure modified sterol II in a periodic process over a long period into the androstenedione in a yield of 50–70%. Immobilized cells of M. phlei have a higher transformation stability in comparison with free intact cells.
In vivo and in vitro recombination of Lambda DNA in CaCl2 transfection
Authors: Betcke A. , Pfeifer M. , Pöhlmann Ch. , Kurth M. , Hartmann M. , Liebscher D.‐H. 
Published: July 2010

AbstractUsing CaCl2 mediated transfection with Lambda DNA fragments, in vitro joining by ligase and in vivo recombination with helper phage DNA are effective systems for generating artificial recombinants. Recombination effiicencies are 20–30% in the in vitro and in vivo recombination systems.At 30 to 37 °C T4 ligase mainly joins natural cohesive λ ends, while at 12 °C the EcoRI‐generated termini are preferentially ligated to form biologically active molecules, if the cloning vector λ 401 is used, which has only one EcoRI target. The ligation products were characterized by gel electrophoresis and CaCl2 transfection.For in vivo recombination a new CaCl2 transfection system was developed, termed postinfectiondependent CaCl2 transfection system, which is based on the infection of recipient cells with helper phages after transfection. In marker rescue experiments using this method not only single but also double recombination occurred between two independent Δ DNA fragments and the helper phage DNA.
Effect of five pesticides on the mycelial growth of some soil and pathogenic fungi
Authors: El‐Hissy F. T. , Abdel‐Kader M. I. A. 
Published: July 2010

AbstractThe effect of three doses (the lowest is the recommended dose in the field) of 5 pesticides namely: Ceresan, Orthocid (fungicides), VCS‐438 (herbicide), and Dursban and Dipterex (insecticides) on the mycelial dry weight of Aspergillus fumigatus, Fusarium moniliforme, Penicillium italicum, and Sclerotium cepivorum was tested 2, 4, 6, 8 and 10 days after treatment. All the pesticides induced inhibition of mycelial growth of the test fungi. Only VCS‐438 at the low dose was stimulatory to F. moniliforme after 4 and 6 days and to P. italicum after 4 days. The rate of inhibition was influenced by the type of fungus, the age of the mycelium, and the dose of the pesticide. At the end of the experiment the two fungicides were detoxified by the test fungi with a rate higher than that of the other pesticides.
Factors which influence CaCl2 dependent transfection of Lambda DNA in Escherichia coli K12 recipients
Authors: Pfeifer M. , Pöhlmann Ch. , Betcke A. , Kurth M. , Liebscher D.‐H. 
Published: July 2010

AbstractThis paper presents further parameters influencing the competence, the process of DNA uptake and the efficiency of plating of CaCl2‐treated E. coli K12 strains. We have found that the process of DNA uptake depends not only on the treatment of bacteria with a certain CaCl2‐concentration but is also influenced considerably by a shift‐down of the CaCl2‐concentration in the reaction mixture. The pH of the growth media and of the reaction mixture plays an important role in maintaining of optimal transfection. The efficiency of plating is influenced by the thickness of the top layer and the concentration of bacteria on the plate.Without genetic variation of the strains, by only varying the mentioned factors we could improve the efficiency of CaCl2 transfection at about two orders of magnitude to a maximum of 6 × 105 pfu/μ DNA.
Wirkung von Ölen und Fettsäuren auf Wachstum und Enzymbildung bei Thermoactinomyces vulgaris II. Methodik der Wachtumsmessung in einer Submerskultur in Gegenwart von Öl
Authors: Leuchtenberger A. , Schaffner B. , Ruttloff H. 
Published: July 2010

AbstractZur Wachstumsmessung einer Kultur des Proteasebildners Thermoactinomyces vulgaris in einem löslichen Nährmedium werden drei Methoden (Bestimmung des Proteingehaltes im Sediment, der Trockensubstanz sowie der Extinktion) hinsichtlich ihrer Reproduzierbarkeit getestet. Dabei wird insbesondere der Einfluß von Rapsölzusätzen – die sich zur Schaumbekämpfung erforderlich machen – auf das Meßergebnis untersucht. Nach den gewonnenen Befunden sind in den Ansätzen ohne Öl alle 3 Methoden, mit Rapsöl hingegen nur die Protein‐ und die Trockensubstanzbestimmung geeignet. Die Streubreite der Ergebnisse ist bei den geprüften Methoden unterschiedlich. Der wachstumsfördernde Einfluß von 0,1% Rapsöl kann in jedem Falle nachgewiesen werden.
Einfluß von Amitrol auf Claviceps fusiformis, Stamm SD 58
Authors: Schmauder H.‐P. , Mater W. , Gröger D. 
Published: July 2010

AbstractThe influence of amitrole (3‐amino‐1.2,4‐triazole) on growth, alkaloid formation and on some aromatic as well as ergoline pathway specific enzymes were studied in Claviceps strain, SD 58. In a phosphate‐rich medium the addition of amitrole can partially reverse the alkaloid‐depressing effect of phosphate. Using a typical fermentation medium amitrole reduces the activities of ergoline specific enzymes but increases drastically tryptophan synthase activity and to a lesser extent transaminases of aromatic amino acids.
Allgemeine Regulation der Aminosäurebiosynthese in Hansenula henricii
Authors: Bode R. , Birnbaum D. 
Published: July 2010

AbstractThe general control of amino acid biosynthesis was investigated in Hansenula henricii. By limitation for single amino acids in wild type strain and mutants no derepression of enzymes was caused. In prototrophic revertants however, obtained from auxotrophic mutants (his, pdx) enzyme activities were 2 – 17 times higher than in the wild type. In these revertants enzymes of the biosynthetic pathways for tryptophan, phenylalanine, tyrosine, arginine, histidine, cysteine, methionine, asparagine, threonine, and isoleucine were derepressed. The amino acid pool pattern of the revertants is completely different from that in the wild type strain. A discussion of possible mechanisms of general control of amino acid biosynthesis in H. henricii is presented.
A mutant of Salmonella typhimurium with an abnormal septation pattern associated with an inhibition of RNA synthesis
Authors: Herrero E. , Guerrero R. , Wolf‐Watz H. , Normark S. 
Published: July 2010

AbstractA mutant strain of S. typhimurium that is disturbed in the regulation of cell division and macromolecular synthesis is described. The life cycle of the mutant can be divided into two discrete stages. When growing in rich medium at a low cell density, cell division is inhibited and the cells filament at the same time as the relative amount of RNA shows a continuous increase. However, at a certain stage, RNA synthesis stops and the filaments start to septate resulting in chain‐formation. These chains can thereafter segregate into individal cells of unit cell length. The accumulation of RNA is rather due to a regulatory defect in the synthesis of the stable RNA species than to an unusual stability of messenger RNA (mRNA)as the half life of mRNA was estimated to 2.3 minutes during the period of RNA accumulation. Latter inhibition of RNA synthesis affects only stable species of RNA. The ppGpp pools of the strain did not fluctuate during growth, showing that inhibition of RNA synthesis is not correlated to changes in the level of ppGpp. Different treatments that reduce the level of transcription such as sublethal concentrations of rifampicin, a shift‐down or high concentrations of nalidixic acid, all induced cell division of filamentous cells, suggesting that there exists an intimate relationship between macromolecular synthesis and cell division. The behaviour of this mutant fits best with the proposed hypothesis that the biomass to volume ratio is of importance in the regulation of cell division in bacteria.
Torulopsis ethanolitolerans n. sp. and T. ethanolitolerans var. minor n. var.
Authors: Rybářová Johanna , Štros F. , Kocková‐Kratochvílová Anna 
Published: July 2010

AbstractA new yeasts. Torulopsis ethanolitolerans and its variety minor, both isolated from industrial sulphite fodder yeast cultivated on synthetic ethanol as the only source of carbon, originally designated R 5. R 6 and the variety R 7, are described. This species differs from all recently accepted Torulopsis species (resp., Candida species), which do not assimilate nitrate, not ferment any sugars, not produce urease, by the assimilation of maltose, but not of sucrose, lactose and D‐xylose.
Laugung von uranhaltigen Phosphoriten mit heterotrophen Mikroorganismen
Authors: Kullmann K.‐H. , Schwartz W. 
Published: July 2010

AbstractThe problem of heterotrophic leaching of metals was tested with uranium‐containing phosphorites under laboratory conditions with regard to possible technical applications. As leaching agents we used the acids of citric and lactic acid fermentation, carried out with a strain of Aspergillus niger in sulfite liquor under different conditions and with lactic acid bacteria in wheye. Up to 12% uranium were soluted with citric acid fermentation of Marocco phosphorite containing 153 ppm U in Aspergillus niger cultures within 27 days.
Effects of methionine sulphoximine on protein transients during heterocyst differentiation in Anabaena and Cylindrospermum spp.
Authors: Grover I. S. , Puri S. 
Published: July 2010

AbstractHeterocystous blue‐green algae normally do not develop heterocysts if grown in the medium enriched with ammonium compounds. If such cultures are resuspended in a medium lacking combined nitrogen, the heterocysts differentiate within 24 h. L‐methionine‐DL‐sulphoximine (MSO) has been reported to induce heterocysts even in the presence of ammonium chloride. The changes in gel electrophoresis protein profiles of cultures developing heterocysts, in the ammonium chloride enriched medium supplemented with MSO suggest that heterocyst differentiation in the presence of ammonium chloride and MSO may be due to derepression of heterocyst formation genes by MSO.
Regulation by repression of urease biosynthesis in Proteus rettgeri
Authors: Zorn C. , Dietrich R. , Kaltwasser H. 
Published: July 2010

AbstractMeasuring the specific enzyme activity in cells of Proteus rettgeri it was shown that urease formation is controlled by repression through ammonia. Derepressed synthesis of the enzyme, as initiated by the absence of ammonia, required an external nitrogen source, which may not only be urea, but also nitrate, glutamate or nutrient broth. In contradiction to earlier reports the observations indicated that urea is not required for the synthesis of this enzyme, and that, therefore, urease is not an inducible enzyme in this microorganism.
AS‐IL—ein neuer, in der DDR aufgefundener Stamm des Cyanophagen AS‐I
Authors: Gorjušin V. A. , Stenz E. , Averkiev A. A. 
Published: July 2010

AbstractIn samples, taken from waters in the surroundings of Leipzig (GDR) in 1978, we found cyanophages in Central Europe for the first time. Among other cyanophages we isolated the new strain AS‐IL. Out of 20 tested cultures of unicellular cyanobacteria seven strains belonging to the genus Synechococcus proved to be susceptible for this cyanophage. In morphology AS‐IL corresponds to the cyanophage AS‐I found in the U.S.A., to which it is related serologically, too. AS‐IL differs from the other strains of AS‐I by a shorter growth cycle, especially a shorter latent period, by the kinetics of inactivation by antiserum, and by a somewhat narrower pH scope of stability. Consequently the isolated cyanophage is to be looked at as a new strain of the cyanophage AS‐I.
Regulation of bistability in glucose metabolism of Escherichia coli ML 30 chemostat cultures by cyclic AMP
Authors: Müller P. J. , Römer W. 
Published: July 2010

AbstractEvidence is presented that cyclic AMP is engaged in the regulation of a bistability in the glucose and energy metabolism of NH3‐limited chemostat cultures of Escherichia coli ML 30. Cyclic AMP probably reverses the repression of the citric acid cycle by glucose favouring the state of glycogen and energy overproduction.
Analysis of genetic markers in new breeding stocks of the yeast Saccharomycopsis lipolytica
Authors: Kurischko Cornelia 
Published: July 2010

AbstractFor development of breeding stocks of S. lipolytica for genetic investigations we isolated and identified several auxotrophic mutants. After selection of strains with normal meiotic segregation pattern for the markers metA, lysA, argA, leuA, uraA, hisA it was shown that the loci metA and lysA and the loci argA and leuA are linked, crossing over frequencies are 25 ± 0.9% and 30 ± 1.2%, respectively.We identified several complementation groups. The marker uraA is allel to ura3 from strains of the Donner Laboratory (USA).These results are the basis for selection of special mutants for forthcoming investigations.The existence of linkage fragments makes it possible to use these strains as tester strains for genetic analysis.
Complex principal component analysis of sea‐level pressure over the eastern USA
Authors: Davis Jerry M. , Estis Frank L. , Bloomfield Peter , Monahan John F. 
Published: July 2010

AbstractThe purpose of this study is to identify preferred areas of synoptic‐scale disturbance activity through the use of the objective analysis technique called complex principal component analysis. This technique is applied to a sea‐level pressure data set consisting of twice daily observations (00 and 12 GMT) for the months January through to March for the years 1973–1976 and 1979–1982. These months were chosen to encompass the time frame of the Genesis of Atlantic Lows Experiment (GALE) 1986. The geographical area studied extended from approximately 30°W to 120°W and 25°N to 60°N.The complex principal component analysis technique allows the detection of propagating features in the pressure data set. The eigenvalues, complex eigenvectors (components), and complex component scores are extracted from an augmented data matrix and are used to compute four measures that define the propagating features within the data set.Research has indicated a spatial relationship between cyclone and anticyclone tracks and the variance in station or sea‐level pressure, especially when the pressure data have been filtered to examine a frequency window traditionally associated with synoptic‐scale activity. The 2–10‐day period was selected for examination of synoptic‐scale activity in this study.The results of the analysis produced four components that could be given a preliminary, physical interpretation. The variability pattern produced by component 1 accounts for the movement of cyclones/anticyclones guided by the mean mid‐tropospheric flow. Component 2 represents the cold air outbreak anticyclones that move south‐eastward into the eastern USA. Component 3 is linked to the cold air outbreaks over the western USA and to cyclone movement in the eastern USA and Canada. Component 4 represents cyclones that move out of the central and southern states to become east coast systems. The results are not without ambiguities, which are discussed.
Interrelationships between Indian and northern Australian summer monsoon rainfall values
Authors: Gregory S. 
Published: July 2010

AbstractRelationships between both the Indian summer monsoon rainfall and the northern Australian summer monsoon rainfall and the Southern Oscillation have been studied previously, and Indian conditions related to Darwin pressure trends, but relationships between the rainfall conditions of the two areas have not been studied. This was effected in terms of generalized regional rainfall values for June‐September for 10 Indian regions and December‐March for four Australian regions. Preceding Australian conditions had virtually no significant correlation with succeeding Indian conditions, but these Indian conditions did show significant correlations with many succeeding Australian regional values. These were examined in terms of simple correlation, quintile tabulation, and multiple correlation and regression, and the more significant relationships were extended further by considering generalized sea‐surface temperature conditions as well. Resultant relationships were evaluated in terms of the 10 years that follow the period of analysis.
A method of agrotopoclimatic division and its practice in China
Authors: Qiyao Lu , Jingming Yu , Baopu Fu 
Published: July 2010

AbstractThe principles, methods, indices, and classification system of agrotopoclimatic division are discussed, as practised for the Shaxi River Basin (SRB) of Fujian Province in China. This paper introduces methods proposed by the authors to calculate the spatial distribution of agroclimatic resources (temperature, humidity, precipitation, and wind speed) in a mountainous area, which may effectively disclose the macro‐ and micro‐variations of the spatial distribution of topoclimate, thereby creating the prerequisites for agrotopoclimatic divisions.
Class—A Canadian land surface scheme for GCMS. I. Soil model
Authors: Verseghy Diana L. 
Published: July 2010

AbstractA new GCM land surface scheme is introduced, incorporating three soil layers with physically based calculations of heat and moisture transfers at the surface and across the layer boundaries. Snow‐covered and snow‐free areas are treated separately. The energy balance equation is solved iteratively for the surface temperature; the surface infiltration rate is calculated using a simplified theoretical analysis allowing for surface ponding. Snow cover is modelled as a discrete ‘soil’ layer.The results generated by CLASS are compared with those of an older model incorporating the force‐restore method for the calculation of surface temperature and a bucket‐type formulation for the ground moisture. Several month‐long test runs are carried out in stand‐alone mode. It is shown that the surface temperature in the old scheme responds more slowly to diurnal forcing and more quickly to longer term forcing than that modelled by CLASS, while its one‐layer representation of soil moisture proves incapable of reproducing changes in the surface fluxes owing to surface variations of moisture content. Finally, the lumped treatment of snow and soil in the old scheme results in an extremely fast disappearance of the snow pack under certain conditions.
Indian summer monsoon rainfall and 200‐mbar meridional wind index: Application for long‐range prediction
Authors: Parthasarathy B. , Kumar K. Rupa , Deshpande V. R. 
Published: July 2010

AbstractVerma and Kamte (1980) and Joseph et al. (1981) identified the association between Indian monsoon rainfall and 200‐mbar meridional wind index for the month of May, and indicated its potential for prediction of the seasonal rainfall.A detailed investigation has been made of this relationship between the monsoon rainfall over India and the meridional wind index (arithmetic average of 200‐mbar meridional wind component for May at Bombay, Delhi, Madras, Nagpur, and Srinagar) based on the data for the period 1964–1988.The relationship between all‐India monsoon (June‐September) rainfall (R) and the wind index (Vm) is negative (correlation coefficient = −0.72) and is significant at the 0.1 per cent level and the regression equation based on this data, for the period 1964–1988, is R = 86.98–2.44 Vm. The stability and consistency of the relationship between rainfall and the wind index have been examined over sliding widths of 15 and 21 years, and the relationship is found to be significant at the 1 per cent level for all windows of 21‐year widths. The meridional wind index shows a good potential in the long‐range prediction scheme of the Indian monsoon rainfall, along with other parameters.
Climatological patterns of thunderstorm activity in south‐eastern USA
Authors: Easterling David R. 
Published: July 2010

AbstractClimatological patterns of summertime thunderstorm activity are examined for most of southeastern USA, excluding the Florida peninsula. Monthly numbers of thunderstorm observations at 61 stations for the period 1951–1977 are analysed by means of principal components analysis (PCA) to identify recurring spatial patterns. The first seven components are found to contain non‐random patterns and are subjected to an oblique rotation. The results indicate that there are approximately six distinct spatial patterns. A high correlation between two of the rotated components and the similarity of their spatial loading patterns implies that they may be manifestations of the same pattern. Months with the highest component scores for each of the first four components are presented as pattern examples, and their upper level circulation patterns are discussed.
Climatic change and future agroclimatic potential in Europe
Authors: Carter T. R. , Parry M. L. , Porter J. H. 
Published: July 2010

AbstractIn this paper, initial results are reported of a study to evaluate the broad‐scale sensitivity of agriculture to climatic change in Europe. The study employs an agroclimatic index, effective temperature sum (ETS), to relate temperature patterns to the cultivable limits of grain maize (Zea mays). A computer mapping system for the European region is adopted to map ETS on the basis both of present‐day and of possible future mean temperatures. In this way, changes in climate can be depicted as geographical shifts of the limit of potential grain maize cultivation.The results indicate that a mean annual temperature increase of only 1°C (within the present‐day range of interannual variability) would open up large areas in southern England, the Low Countries, eastern Denmark, northern Germany and northern Poland to potential maize cultivation. An increase of 4°C would move the limit into central Fennoscandia and northern Russia. These represent rates of northward shift of approximately 200–350 km °C−1 in western Europe and 250–400 km °C−1 in eastern Europe. Comparison of these shifts with those estimated on the basis of general circulation model (GCM) projections of future temperatures suggests that a 1°C warming will be achieved well before the time the global climate responds fully to an equivalent doubling of atmospheric carbon dioxide, possibly as early as 2010. Shifts comparable with those for a 4°C warming are achieved under all the GCM scenarios of doubled CO2, occurring perhaps as soon as 2050 if the current growth in emission rates of greenhouse gases were to continue unabated. The rate of shift of the grain maize limit implied for this (high) emissions scenario is in the order of 150–200 km per decade over the next 70 years, slower than this during the next few decades, but faster thereafter.Such shifts would offer new opportunities for farmers in different regions of northern Europe. However, given the possible rapidity of the shifts, in order for these opportunities to be exploited successfully immediate attention should be directed towards more detailed assessments of crop potential in regions identified as currently marginal for grain maize.
Distribution and intensity of frontal rainfall over greece
Authors: Flocas A. A. , Giles B. D. 
Published: July 2010

AbstractThe amounts and intensities of rainfall are related to each front that crossed Greece during the period 1971–1981 by using synoptic messages from 26 meteorological stations and from 26 autographic rain‐gauges. The fronts were related to five depression tracks described by Flocas. The amount of rainfall was considered for periods of 15, 30, and 60 minutes and related to slight, moderate, heavy, and violent intensities. This information will provide a climatological background to forecasts of frontal rainfall.