bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of previous growth conditions on starvation survival and endogenous metabolism rate of Arthrobacter fluorescens
Authors: Cacciari Isabella , Lippi Daniela , Pietrosanti Tito , Pietrosanti Walter 
Published: February 2007

AbstractThe starvation survival and the endogenous metabolism rate were studied in cultures of Arthrobacter fluorescens grown at various dilution rates under ammonium‐limited conditions. In addition, the ammonium‐limited cultures grown at dilution rates of 0.03 and 0.20 h−1 were made oxygen‐limited and these cultures were also studied. Suspensions of washed cells from all the steady state cultures were incubated under total nutrient deprivation at 30°C for 20 days. The effects of starvation on cell counts, protein and carbohydrate contents and endogenous respiration rates were determined. Viable cell count of suspensions grown under ammonium‐limited conditions declined faster for the cells grown at faster dilution rates. On the contrary starved slow growing oxygen‐limited cells showed a more rapid decrease in viability than the fast growing ones. Cell dry weights, carbohydrates and proteins declined exponentially during starvation and their rates of change were generally greater with cells grown at higher dilution rates, irrespective of nutrient limitation. Starved oxygen‐limited cultures exhibited a higher death rate and a greater reserve material mobilization than ammonium‐limited cultures grown at the same dilution rate.
Characterization of a methanol‐utilizing sulfate‐reducing bacterium isolated from a wastewater pond
Authors: Hard Barbara C. , Babel Wolfgang 
Published: February 2007

AbstractA methylotrophic, mesophilic, gram‐negative sulfate‐reducing bacterium, named strain UFZ B378, was isolated from the sediment of a wastewater pond of a derelict sugar factory. The rod shaped to slightly curved cells are motile and 1.5 to 3.5 um long and 0.5 um wide. Formation of spores was not observed. The G+C content of the DNA was 58.7 mol%. Sulfate is used as electron acceptor, methanol can be used as sole source of carbon. Other electron donors included pyruvate, lactate, acetate, ethanol, butanol, propanol, choline, betaine, succinate, fumarate and benzoate without the addition of H2. Growth occurred from pH 4 to 9.0, the optimum pH was found to be around 7.0. The temperature range for growth was between 3°C and 40°C, with an optimum at 30°C. Vitamins or other supplines were not required. The strain was found to be tolerant to ferric and ferrous sulfate (5 mM and 100 mM respectively) on their own and in combination in the culture medium. The pH in batch cultures with methanol increased from 6.3 to 8.0 over a period of 48 days due to the reduction of sulfate and formation of hydrogen sulfide. Production of methane was not found.
Production of α‐galactosidase by Lactobacillus plantarum isolated from diverse sources
Authors: Sanni I. A. , Ahrne S. , Onilude A. A. 
Published: February 2007

Abstractα‐Galactosidase activity was observed in six strains of Lactobacillus plantarum isolated from fermented cereal products, human intestinal flora and fermented tea. The cultural conditions under which the enzyme activity was detected suggest that the enzyme is inducible. Development of mutants in four out of the six strains was observed and the mutants recorded high enzyme activity than the parent strains. Effect of different carbohydrates on enzyme activity showed glucose and raffinose being repressive in the parent strains. Although all the carbohydrate sources supported growth, highest amount of enzyme activity was recorded on lactose and glucose. The enzymatic potential of L plantarum in reducing flatulence properties of the raw material base of some West African fermented foods is suggested.
The effect of ultrasound on Escherichia coli viability
Authors: Allison D. G. , D'Emanuele A. , Eginton P. , Williams A. R. 
Published: February 2007

AbstractThe effect of continuous‐wave ultrasound on the viability of Escherichia coli HB101 was assessed using a 20 kHz ultrasonic processor. A standardised cell suspension of fixed concentration was used to investigate the influence of different physical and environmental conditions on ultrasound susceptibility. Cell viability decreased exponentially with time at different intensities of ultrasound. Increasing intensity caused a decrease in decimal reduction times. Loss of cell viability occurred primarily from the mechanical effects of ultrasound rather than free radical damage. E. coli susceptibility was also shown to vary with growth conditions, whereby cells cultivated either on agar or harvested from the stationary phase of liquid culture were significantly more susceptible to ultrasound than an equivalent population obtained from the exponential phase of liquid growth. The implication of these results is discussed in relation to the use of ultrasound as a novel means of bacterial transformation.
Decolorisation of the polymeric dye Poly R by Streptomyces viridosporus T7A
Authors: Ball A. S. , Colton J. 
Published: February 2007

AbstractThe ability of a range of actinomycetes to decolorise the polymeric dye Poly R was investigated. Three well characterised lignocellulose‐degrading actinomycetes, Streptomyces viridosporus, Streptomyces badius and Thermomonospora mesophila were found to be the most efficient at decolorising Poly R, with a maximum decolorisation rate of 0.10 unit per day. Extracellular fractions taken from S. viridosporus grown on a variety lignocellulose‐related substrates were also capable of decolorising Poly R, indicating that dye decolorisation was not merely due to biomass uptake. The activity of extracellular fractions from straw‐grown cultures of S. viridosporus was three to six times greater than those from other substrates examined. Purification of this dye‐decolorising activity from S. viridosporus using anion exchange chromatography revealed the presence of a single active fraction. This was confirmed using gel permeation chromatography which estimated the molecular mass of the decolorising protein to be approximately 30000 Da.
Biosynthetic capacities of actinomycetes. 5. Dioxolides, novel secondary metabolites from Streptomyces tendae
Authors: Blum Sabine , Groth Ingrid , Rohr Jürgen , Fiedler Hans‐Peter 
Published: February 2007

AbstractDioxolides, a novel class of secondary metabolites were detected by a HPLC‐diode array screening technique in the culture filtrate of Streptomyces tendae Tü 4042. The compounds show no biological activity against Gram‐positive and Gram‐negative bacteria, yeasts and fungi. Besides dioxolides, which consist of an unusual substituted dioxolane ring, anhydroshikimate and para‐hydrobenzamide were detected by this technique. Both compounds were not yet described as natural products.
The isolation of Akabane virus (Iriki strain) from calves in Taiwan
Authors: Liao Y. K. , Lu Y. S. , Goto Y. , Inaba Y. 
Published: February 2007

AbstractNonsuppurative encephalitis in calves aged 4–12 months, cow abortion and fetal deformities were endemic in dairy farms in Taiwan in recent years. A virological investigation emphasizing on Arthpodborn virus (Arbovirus) was conducted. Total of 11 strains of Akabane virus were isolated from endemic districts between June and July of 1992. Among them, seven viruses were isolated from blood samples of 15 calves showing nervous signs. Another 4 Akabane viruses were isolated from clinically healthy calves from three of six dairy farms investigated. All the six investigated farms had a recent history of abortion and fetal deformities. The isolates caused prominent cytopathic effects in HmLu‐1 cells and could reach a high virus titers (5 × 106 TCID50/ml). As demonstrated by a cross neutralization test, the isolates had identical antigenicity to Iriki strain of Akabane virus, but were antigenically more distant to JaGar‐39 and OBE‐1 strain of Akabane virus. This is the first report on the isolation of Akabene virus in Taiwan, and also the second report on the isolation of Iriki virus in the world.
Microbiological status of selected chicken carcases from a non‐automated poultry processing plant
Authors: Olivier Maretha , Veary C. M. , Cloete T. E. , von Holy A. 
Published: February 2007

AbstractThe microbiological status of chicken carcases sampled at three different processing points in a South African Grade B poultry abattoir slaughtering ca. 750 birds per hour, was determined. Six skin samples and two meat samples were aseptically collected from different sites on each carcase. Total bacterial counts were performed at 25 °C, 37 °C and 43 °C and all colonies from plates showing between 30 and 300 cfu were characterised. Bacterial counts of the skin samples at 37 °C were consistently the highest, followed by those at 25 °C and then 43°, but for the two meat samples the highest bacterial counts were found at 37 °C and the lowest at 25 °C. Neck skin counts were marginally higher than bacterial counts of the other skin samples. The Gram negative genera Escherichia and Acinetobacter were isolated most frequently at all three incubation temperatures and from all sampling sites, while the dominant Gram positive genera were Staphylococcus and Enterococcus. Escherichia isolates predominated on the skin sampling site cranio‐dorsal to the pygostyle, whilst Staphylococcus isolates predominated on the skin sampling site caudal to the breastbone. Microbiological contamination is a major problem in the abattoir studied and further studies should therefore aim to determine points of maximum contamination in the processing line.
Diversity of microfungi in the sandy soil of Ipanema Beach, Rio de Janeiro, Brazil
Authors: De Moura Sarquis Maria Inez , De Oliveira Pedrina Cunha 
Published: February 2007

AbstractThe mycobiota of the sandy soil of Ipanema Beach, Rio de Janeiro, Brazil, was investigated in 144 sand samples collected at four different sites along the sea coast, divided into three subsites. for a period of one year. A total of 4285 yeast colonies and of 6956 of colonies filamentous fungi were isolated using conventional media and techniques. Representatives of the filamentous fungi corresponding to a total of 1334 colonies were identified and assigned to 34 genera and 170 species. The genera of highest incidence and their respective numbers of species were as follows:Aspergillus, 30.4%, 32 spp.;Penicillium, 16.2%, 35 spp.;Fusarium, 12,6%, 33 spp.:Trichoderma, 6.4%, 7 spp.;Paecilomyces, 3.7%, 10 spp.:Cladosporium, 3.1 %, 8 spp. andAcremonium, 1.0%, 8 spp. Several other genera and species were detected at quite low occurrences. Non‐sporulating fungi (18.3%) and Coelomycetes (Sphaeropsidales) (1.9%) were also detected. Most of the genera detected belonged to theDeuteroycotina, with fewer proportions belonging to theAscomycotinaandZygomycotina.Moniliaceaewas represented by the largest number of species andDematiaceaewas represented by the largest number of genera. In terms of seasonal distribution, the largest number of filamentous fungi was isolated during the winter and the smallest number the Summer.
Molecular investigations on the dilemma of nitrogen‐fixing characteristics of Azotomonas
Authors: Lee Saehong , Pulakat Lakshmidevi , Hausman Bryan S. , Efuet Ekem T. , Lei Shi , Gavini Narasaiah 
Published: February 2007

AbstractThe ability of Azotomonas to reduce atmospheric nitrogen has been an issue of controversy since this genus was included in the family Azotobacteraceae. Here we report the investigations on the nitrogen fixation characteristics of Azotomonas fluorescens strain ATCC13544 and show that it can grow in both liquid medium and on solid agar plates made with modified BURK nitrogen‐free medium supplemented with ammonium acetate as a nitrogen source. In contrast, when ammonium acetate was omitted from this medium, the cells did not show any noticeable growth. Southern blotting analysis of the chromosome of Azotomonas strain ATCC13544 did not show any hybridization with a probe made of DNA sequences corresponding to the nifH gene of Azotobacter vinelandii. Based on these results, we conclude that the Azotomonas fluorescens ATCC13544 does not contain the conventional genetic information on its chromosome that is needed to utilize atmospheric nitrogen as the sole source nitrogen to support its growth.
The presence of glutamine synthetase in the thylakoids of nitrogen‐fixing cyanobacterium Nostoc muscorum
Authors: Sallal Abdul Karim J. 
Published: February 2007

AbstractThe intracellular distribution of glutamine synthetase (GS) in cell‐free extracts of Nostoc muscorum has been investigated. 64–73% of the enzyme activity was associated with the thylakoid membranes. No enzyme activity was found in cytoplasmic membranes. 92% inhibition of the enzyme activity was obtained with an antiserum raised to the thylakoids using Triton‐treated membranes, in comparison to 7.95% inhibition with the intact membranes. This suggests that the majority of the enzyme is embedded inside these membranes. This was also supported by the effect of pronase on the exposed glutamine synthetase using intact membranes.
Fungal spore concentrations in the atmosph at the Anatolia quarter of Istanbul, Turkey
Authors: Çolakoglu Günay 
Published: February 2007

AbstractIn this research, spore concentrations ofCladosporium, Alternaria, Epicoccum, Botrytis, Leptosphaeria, Polythrincium, ascospores, Aspergillits, Penicillium, basidiospores, uredospores,Ustilago, Torula, Erysiphe, Ganoderma, Hyaline indeterminateand others in the atmosphere have been determined, and comparisons have been made between locations with both low and high spore concentrations. The importance of these air‐borne fungal spores which cause allergy and asthma are emphasized in the paper from the viewpoint of human health.
Some factors affecting endo‐β‐1,4‐glucanase production by two Bacillus strains isolated from Zimbabwean hot springs
Authors: Mawadza Crispen , Zvauya Remigio 
Published: February 2007

AbstractTwo Bacillus strains capable of producing endo‐β‐1,4‐glucanase enzyme were isolated from Zimbabwean hot springs. Strain HR68 produced the enzyme when cultured using both carboxymethylcellulose (CMC) and simple sugars as carbon source while strain CH43 produced the enzyme on CMC only. The optimum conditions for enzyme production were an initial pH of 6 and a temperature of 50 °C for strain HR68 while for strain CH43 the optimum conditions for enzyme production were an initial pH of 5 and a temperature of 50 °C. A fall in enzyme production was observed after about 4 to 8 h of growth for both isolates. The fall in production coincided with a rise in proteolytic activity in cultures of both isolates. Strain HR68 produced endo‐β‐1,4‐glucanase when grown in continuous culture using glucose as the carbon source.
Proteolytic activities in cultures of selected white‐rot fungi
Authors: Staszczak Magdalena , Nowak Grzegorz , Grzywnowicz Krzysztof , Leonowicz Andrzej 
Published: February 2007

AbstractThe presence of multiple intracellular and extracellular proteolytic activities in trophophasic (nutrientrich) and idiophasic (carbon‐or nitrogen‐starved) cultures of the white‐rot fungi Trametes versicolor and Phlebia radiata was demonstrated by electrophoresis on polyacrylamide gels containing denatured haemoglobin as a substrate. In the trophophasic cultures of T. versicolor, seven electrophoretically distinguishable proteases were defined using mycelial extracts and six (three clear and three less intensive) of secreted proteases. For P. radiata eight bands of intracellular and five bands (one distinct and four less active) of extracellular proteolytic activities were detected. Gel electrophoresis revealed changes in patterns of secreted and mycelial proteinases upon carbon or nitrogen deprivation. The changes were seen both as an increase in activity of certain bands and as the appearance of new proteolytic bands. Specific activities of extracellular proteinases, assayed under idiophasic (—C or —N) conditions, increased 2—3 fold as compared to those upon nutrient sufficiency. These changes accompanied a shift to secondary metabolism and onset of ligninolytic activity.
Enantiospecific reduction of prochiral ketones of aromatic type to optically active alcohols inNigrospora oryzaeculture
Authors: Jarosz Bogdan , Siewiński Antoni 
Published: February 2007

AbstractThe culture ofNigrospora oryzaereduces twelve prochiral ketones of homo‐ and heteroaromatic type (acetophenone, 3‐ and 4‐methylacetophenone, 4‐nitroacetophenone, propiophenone, 2‐acetylnaphtha‐lene, 2‐acetyltiophene, 2‐ and 4‐acetylpyridine,α,α,α‐trifluoroacetophenone, α‐tetralone, 4‐benzoyl‐pyridine) enantiospecifically to corresponding optically active alcohols. The enantiomer of S configuration is in nine cases predominant, R configuration was found in three alcohols. The degree of chemical reduction determined in GC ranged from 20% to almost 100%, while optical purity was from 5% to 100% ee. It is worth noting that the same culture did not reduce 4‐aminoacetophenone, 2‐acetylpyrrole and 2‐acetylindole.
Alnus incana response on treatment with fluorescent Pseudomonas sp. strain 267
Authors: Małek Wanda 
Published: February 2007

AbstractFluorescent Pseudomonas sp. strain 267 was evaluated for its ability to stimulate the growth of A. incana in vitro under gnotobiotic and nongnotobiotic conditions, as well as in the presence and absence of FeCl3 as iron source. Bacterization of grey alder roots with Pseudomonas sp. strain 267 promoted plant growth under each of the studied conditions. The dry weight of leaves and roots increased significantly when compared with the uninoculated plants. Chlorophyll concentration in the leaves of grey alder, treated with fluorescent pseudomonad, was positively correlated with plant growth stimulation. Its concentration showed 50% increase over the control uninoculated plants. Moreover, it is supposed, that A. incana growth promotion by Pseudomonas sp. strain 267 may result from secretion of vitamins by this bacterium, which can be utilized by plant.
Soluble cell‐bound and extracellular cyclodextrin glycosyltransferases of Bacillus macerans show identical enzymological characteristics and antigenicity
Authors: Nógrády Noémi , Pócsi István , Katona Éva , Jeney Viktória , Boross Péter , Tözsér József , Fachet József , Szentirmai Attila 
Published: February 2007

AbstractSoluble cell‐bound and extracellular cyclodextrin glycosyltransferases of Bacillus macerans were purified to homogeneity using the subsequent steps of adsorption on starch, ion‐exchange chromatography and gel filtration. The elution profiles and the relative molecular masses of the enzymes as well as their N‐terminal sequences were found to be identical. Moreover, mouse monoclonal antibodies raised against the soluble cell‐bound enzyme recognised equally well both the cell‐bound and the extracellular enzyme preparations. Regarding that no signal peptide could be detected in either the cell‐bound or the extracellular cyclodextrin glycosyltransferase the enzyme was probably entrapped between the cell membrane and the cell wall in the early stationary phase and was released during cell lysis without any modification.
Phylogenetic relationships of entomopathogenic nematophilic bacteria: Xenorhabdus spp. and Photorhabdus sp.
Authors: Suzuki Tomonori , Yabusaki Hiroaki , Nishimura Yukimasa 
Published: February 2007

AbstractPhylogenetic relationships of Xenorhabdus spp. and Photorhabdus sp. were investigated on the basis of 16S rRNA gene sequences. Xenorhabdus spp. and Photorhabdus sp. were grouped together with Proteus vulgaris and Arsenophonus nasoniae. This group was distant from other members of the family Enterobacteriaceae. Xenorhabdus japonicus, previously proposed as a new species, was nearly located to Xenorhabdus nematophilus. Signature nucleotides of X. japonicus were identified that distinguish it other members of the family Enterobacteriaceae.
Evaluation of defined media suitable for isolation of auxotrophic mutants of mycobacteria
Authors: Wards Barry J. 
Published: February 2007

AbstractIn order to investigate the production of auxotrophs of slow growing mycobacterial pathogens, an evaluation of defined liquid and solid media suitable for Mycobacterium tuberculosis, Mycobacterium bovis and Mycobacterium paratuberculosis was undertaken. Five defined liquid media were evaluated. A number of solid support matrices was added to the liquid media to produce solid media for evaluation. Tween 80 was added to all media to produce diffuse homogeneous growth. Although satisfactory growth in defined liquid media was achieved with all strains tested, poor growth was generally observed in the equivalent defined solid medium for strains belonging to the tuberculosis complex. Only M. paratuberculosis produced satisfactory growth on defined solid media, especially on Middlebrook 7H9. The inhibitory effect of Tween 80 and the presence of inhibitory factor(s) in agar were confirmed. Partial removal or inactivation of these factors by the addition of absorbents to the media was achieved.
A pullulan‐degrading enzyme activity of Aureobasidium pullulans
Authors: West Thomas P. , Strohfus Beth 
Published: February 2007

AbstractA pullulan‐degrading enzyme activity was detected in the culture medium after growth of the fungus Aureobasidium pullulans on corn syrup as a carbon source. The product of pullulan catabolism by this activity was determined to be glucose. The highest specific activity of this enzyme was found after 7 days of fungal growth. Although α‐amylase activity was not detectable, the presence of a glucoamylase activity was indicated. It appeared that the enzyme responsible for pullulan degradation was likely glucoamylase B.
Steroid transformation by mutants of Mycobacterium sp. with altered response to antibiotics
Authors: Barthakur Sharmistha , Roy Monoj K. , Bera Saphal K. , Ghosh Anil Ch. 
Published: February 2007

AbstractMycobacterium sp. NRRLB3683 which is capable to convert β‐sitosterol to 1,4‐androstadiene‐3, 17‐dione (ADD) was treated with methyl methane sulfonate and two strains with altered sensitivity to various antibiotics were obtained. One of the strain was steroid 1(2)‐dehydrogenase negative and the other positive. Efficiency of utilization of sterols followed the order β‐sitosterol > cholesterol > soluble cholesterol. The steroid 1(2)‐dehydrogenase negative strain was capable of producing 17KS (AD) from β‐sitosterol and converting AD to testosterone and ADD to AD suggesting the negative role of 1(2)‐dehydrogenase in sterol side chain cleavage and decrease in hydrogenase activity by mutation. But this enzyme can perform the reverse reaction under aerobic condition.
Mould counts in the atmosphere at the Europe Quarter of Istanbul, Turkey
Authors: Çolakoglu Günay 
Published: February 2007

AbstractDaily mould counts were made using both exposed slides and Petri dishes, from January 1, 1994 to December 31, 1994 in Europe Quarter of Istanbul, Turkey. The most important moulds were: Cladosporium, Alternaria, Penicillium, Aspergillus and yeast. The peak mould season was early January to early February. Some moulds were present all year.
Differentiation of Rhodococcus species by ribotyping
Authors: Jorks Siegfried 
Published: February 2007

AbstractThe ribosomal RNA gene restriction patterns (ribotyping) was investigated with respect to the characterization of Rhodococcus species and R. rhodochrous strains. Chromosomal DNA was prepared, digested with BamH I, blotted, and hybridized with acetylaminofluorene‐labelled 16 + 23S rRNA from E. coli. The type strains of seven Rhodococcus species studied gave different hybridization patterns in each case. All strains tested were clearly distinguishable by ribotyping. Patterns contained two to eight bands between 1.4 kb and 11.8 kb and demonstrated the high genetic divergence of genus Rhodococcus. Investigation of nine R. rhodochrous strains resulted in patterns with seven or eight bands. One fragment. 4.4 kb in size, was common to all R. rhodochrous strains and appears to be characteristic of R. rhodochrous. Ribotyping was evaluated as a tool for distinguishing between Rhodococcus species.