bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evidence for and characterization of cytochrome P‐450 in Neurospora crassa
Authors: Nega Eva , Grunwaldt Gisela 
Published: February 2007

AbstractCytochrome P‐450 was detected in microsomes and presumably in cytosol of Neurospora crassa, and was found to be inducible by progesterone. In the microsomal fraction cytochrome b5 and NADPH‐cytochrome c reductase activities were measurable, too. Cytochrome P‐450 of Neurospora crassa is inhibited by SKF‐525 A and by inhibitors of ergosterol biosynthesis. After induction of cytochrome P‐450 with progesterone 11α‐hydroxyprogesterone as one metabolite of progesterone was detected in the culture media as well as in the mycelia. After 42 hours about 70% of progesterone were metabolized.
In vitro studies on antifungal activity of tea (Camellia sinensis) and coffee (Coffea arabica) against wood‐rotting fungi
Authors: Arora D. S. , Ohlan D. 
Published: February 2007

AbstractThe present study reports the sensitivity of ten different wood‐rotting fungi towards eight samples of tea and two samples of coffee. The tea samples included five CTC black teas, one orthodox black tea and two green teas. The different fungi tested were sensitive to different tea and coffee samples to variable levels. Green tea caused the maximum growth inhibition and it was 100% in case of Phanerochaete chrysosporium and Sporotrichum pulverulentum. Of the black tea samples, orthodox black tea was more effective inhibitor for all the fungi tested. Phlebia radiata was the most sensitive fungus to all the black tea samples except Lipton Cheers. The growth of Daldinia concentrica was least affected by all the black tea samples. The two coffee samples showed better inhibition than CTC black tea samples. The inhibitory effect of tea and coffee extracts was greatly reduced on their filtration. All the tea and coffee samples tested showed more than 50% reduction in their inhibitory activity. The inhibitory effect was completely lost in spent black tea leaves. The antifungal effect of pure caffeine was tested at different concentrations. Majority of the fungi were totally inhibited at a concentration of 0.3% whereas, D. concentrica, P. radiata and P. palustris showed complete inhibition at a concentration of 0.5 percent.
Characterization of a bacterial consortium degrading the lignin model compound vanillyl‐β‐D‐glucopyranoside
Authors: Céspedes Ricardo , González Bernardo , Vicuña Rafael 
Published: February 2007

AbstractAryl‐β‐D‐glycosides have been described as intermediates in lignin biodegradation. The catabolism of this kind of compounds has been poorly studied. In this work, the isolation and initial characterization of a bacterial consortium degrading vanillyl‐β‐D‐glucopyranoside is reported. The consortium is able to grow on and completely degrade the dimer vanillyl‐β‐D‐glucopyranoside. The consortium is composed of three microorganisms: strain 2.1 is closely related to Chryseomonas luteola; strain 2.2, identified as Moraxella phenylpyruvica and strain 2.3, preliminary identified as Pseudomonas spp. Complete degradation of the glycoside required strains 2.1 and 2.2, although only strain 2.1 was able to cleave the aryl‐glycoside linkage. Oxidation of vanillyl alcohol, one product of the aryl‐glycoside cleaving reaction, to the respective acid was carried out by strain 2.2. Vanillic acid was used as growth substrate by strains 2.2 and 2.3. Strain 2.1 can grow on other aryl‐β‐glycosides, accumulating the aryl moiety in the culture. β‐Glucosidase present in strain 2.1 is probably the key enzyme in the catabolism of aryl‐glycosides by this consortium.
Phenoxyacetic acid induces glutathione‐dependent detoxification and depletes the glutathione pool in Penicillium chrysogenum
Authors: Emri Tamás , Pócsi István , Szentirmai Attila 
Published: February 2007

AbstractEnzymes of the glutathione‐dependent detoxification pathway (glutathione S‐transferase and γ‐glutamyl‐transpeptidase)1) were induced, and the glutathione pool was completely depleted by phenoxyacetic acid in Penicillium chrysogenum mycelia incubated for 15 h in a culture medium containing lactose as a carbon source and sodium glutamate as a nitrogen source. A significant increase in both the oxidised glutathione concentrations and the glutathione reductase activities were also observed. 1‐Chloro‐2,4‐dinitrobenzene ‐ a potent substrate and inducer of glutathione S‐transferase ‐ initiated very similar physiological changes but no β‐lactam production could be detected in this case. When (NH4)2HPO4 was used as a nitrogen source the penicillin biosynthesis was repressed and the induction of γ‐glutamyltranspeptidase by phenoxyacetic acid was hindered considerably.
Effect of the carbon source succinate on pyrimidine synthesis in Burkholderia cepacia
Authors: Li Ke , West Thomas P. 
Published: February 2007

AbstractThe effect of the carbon source succinate on pyrimidine synthesis in the pathogen Burkholderia cepacia ATCC 25416 was investigated. The five de novo pathway enzyme activities of pyrimidine biosynthesis in B. cepacia were shown to be affected when ATCC 25416 cells were grown in the presence of uracil. Pyrimidine limitation of a uracil auxotrophic B. cepacia strain lacking orotidine 5′‐monophosphate decarboxylase activity increased aspartate transcarbamoylase, dihydroorotase, dihydroorotate dehydrogenase and orotate phosphoribosyltransferase activities by at least 1.5‐fold which indicated that these pathway enzymes may be regulated by a uracil‐related compound. The levels of the de novo pyrimidine biosynthetic enzyme activities in B. cepacia ATCC 25416 cells appeared to be influenced to a greater degree in cells grown on succinate than on glucose as a carbon source.
Heavy metal resistant Arthrobacter sp. — A tool for studying conjugational plasmid transfer between Gram‐negative and Gram‐positive bacteria
Authors: Margesin R. , Schinner F. 
Published: February 2007

AbstractThe role of two heavy metal‐resistant strains of the Gram‐positive genus Arthrobacter sp. as a tool in studying conjugational plasmid transfer between Gram‐positive and Gram‐negative bacteria is described. The high nickel resistance and the cobalt resistance of Arthrobacter sp. strain RM1/6 could be transferred to Arthrobacter sp. strain WS14. IncQ plasmids (pKT240, pKT240::czc, pML10) could be mobilized from E. coli into Arthrobacter spp. strains; antibiotic (Km, Ap, Tc)1) and heavy metal (Co) resistance genes were expressed in the recipient strains. IncQ plasmid pKT240 could be mobilized between Arthrobacter spp. strains. IncP plasmid RP4::Tn4371 was transferred from A. eutrophus to Arthrobacter sp., RP4‐mediated antibiotic resistance to Km was expressed in the recipient strain.
Evaluation of the Staph‐Zym system in the identification of staphylococci isolated from ovine milk and the ewe environment
Authors: Burriel Angeliki Rothi , Scott Maggie 
Published: February 2007

AbstractThe Staph‐Zym and the Rosco Set methods were used to assign species to 142 strains of staphylococci isolated from the milk of sheep with subclinical intramammary infection or teat skin, mouth of lambs or milking machine teat cups. One hundred eleven of the same strains were also tested by Standard Laboratory Culture Media. The Rosco Set assigned species to all strains tested, but the other two methods were unable to assign species to a similar proportion of isolates. Seventy six (68.5%) of the strains tested with all three methods were not assigned the same species, each method shown a preference for particular species. The Staph‐Zym and the Rosco Set identified most of the strains as members of the ‘epidermidis’ group with the ‘aureus’ second, while the reverse was observed with the Standard Laboratory Culture Media. Only in the case of Staphylococcus epidermidis all methods were in close agreement. When the results of the Staph‐Zym and the Rosco Set are compared, although they agree on the predominant group, they disagree on the predominant species within the same group.
Relationship between the thermotolerance and the increase of DnaK and GroEL synthesis in Enterococcus faecalis ATCC19433
Authors: Flahaut Sigrid , Frere Jacques , Boutibonnes Philippe , Auffray Yanick 
Published: February 2007

AbstractRelationship between intrinsic thermal resistance, thermotolerance and heat shock proteins (hsp) synthesis is studied in Enterococcus faecalis. We showed that an impressive phenotypic heat resistance was induced by mild heat and a slight thermotolerance was developed by various sublethal pretreatments such as NaCl, SDS and bile salts. Hydrogen peroxide, acid and alkalin shifts or ‘thermomimetic’ agent such as ethanol, did not enhance the survival of adapted cells against the lethal thermal shock (62 °C). The inhibition of protein synthesis by chloramphenicol or rifampin abolished thermotolerance. The immunological identification of the DnaK and GroEL proteins in E. faecalis allowed to study induction of these molecular chaperones under various conditions. Heat was the most efficient inductor of DnaK and GroEL synthesis. However, it was surprising that ethanol did not strongly induce these proteins. We also show that amplification of these hsp is not correlated to acquired thermotolerance with a linear relationship. A weak thermotolerance is not coupled from increased synthesis of DnaK and GroEL. So, we postulate that the high synthesis of the major hsp is not obligatory in the thermal cross‐protection but that de novo protein synthesis is an absolute necessity in E. faecalis. Activation of preformed hsp or other factors depending or not on protein synthesis may be also necessary to enhance thermal resistance.
UV‐B and heat shock‐induced changes in the wild type and UV‐B heat shock‐tolerant (UV‐HSt) strain of the unicellular cyanobacterium Anacystis nidulans
Authors: Gour R. K. , Singh S. , Pandey P. K. , Bisen P. S. 
Published: February 2007

AbstractUltraviolet‐B and heat shock (HS)1) induced changes in growth kinetics, NO−3 reductase (NR), glutamine synthetase (GS), NO−3 uptake and NO−2 efflux activities, have been studied in the wild type Anacystis nidulans and its UV‐HS1 strain. The application of UV‐B and HS stresses either used separately or in combination shows a drastic changes in growth rates of wild type, and insignificant effect on the growth of the UV‐HSt strain. The wild type cells, in contrast to its UV‐HSt strain exhibits insignificant effect on NR and GS activities upon UV‐B radiation followed by heat shock treatment. Similar treatments to the wild type cells resulted in maximum reduction of NR and GS activities. The NO−3 uptake and NO−2 efflux activities are found to be lower in the UV‐HSt strain than in the wild type counterpart and both the systems consisted of an initial rapid phase followed by a slower one. NH+4 grown cells when transferred to NO−3 medium in presence of streptomycin showed significant inhibition in the development of both the NO−3 uptake and NO−2 efflux systems indicating that de novo protein synthesis is required for the development of NO−3 uptake and NO−2 efflux systems. Whereas the same cells in the presence of L‐methionine‐DL‐sulfoximine (MSX) showed marginally higher NO−3 uptake but, exhibits only 42% NO−2 efflux to that of MSX‐devoid both the cells. It is suggested that NH+4 assimilation via GS is necessarily required for NO−2 efflux system to be functional.
Purification and properties of methanol dehydrogenase from Methylocystis sp. GB 25
Authors: Grosse Stephan , Wendlandt Karin‐Dagmar , Kleber Hans‐Peter 
Published: February 2007

AbstractMethanol dehydrogenase (MDH) from Methylocystis sp. GB 25, which belongs to the group II of methanotrophic bacteria, is able to catalyse the oxidation of methanol to formate directly. The enzyme was purified 20‐fold by a 5 step procedure to electrophoretic homogeneity. After cell disruption by French press, about 95% of MDH‐activity was found in the soluble fraction. The relative molecular mass of the native enzyme has been estimated to be 122 kDa by gel filtration and 115 kDa by the method of HEDRICK and SMITH (1968). It seems to be composed of two identical subunits with a relative molecular mass of 62 kDa (estimated by SDS gel electrophoresis). The isoelectric point was found to be about 8.3. The amino terminal sequence shows a strong similarity to the α‐chain of MDH from the facultative methylotrophic bacterium Methylobacterium extorquens AM1. PQQ, the probable prosthetic group of MDH, could be detected in the supernatant of the culture by using the apoenzyme of a membrane‐bound glucose dehydrogenase from Pseudomonas aeruginosa but not absolutely in the absorption spectra of the enzyme after DEAE‐chromatography. The purified MDH has an optimum activity at pH 9.0 and at 45 °C. MDH of Methylocystis sp. GB 25 oxidises only primary alcohols from methanol to heptanol and aldehydes from formaldehyde to propionaldehyde and the glutaraldehyde, respectively. The estimated Km‐values show no dependence upon the chain length of substrates.
Physiological and biochemical characterization of intergeneric hybrids of thermotolerant and non‐thermotolerant yeasts
Authors: Dhamija S. S. , Gera R. , Singh D. K. , Singh D. , Marchant R. 
Published: February 2007

AbstractKluyveromyces‐like intergeneric hybrids of thermotolerant Kluyveromyces marxianus and non‐thermotolerant Saccharomyces cerevisiae, produced in a previous study by protoplasmic fusion, have been characterized. On molasses, these strains produced ethanol in excess of 6% (v/v) both at 30 and 45 °C as against 3% and 4.2% (v/v) by the former parent at 30 and 45 °C, respectively. In hybrids, the increase in ethanol production appeared to be a sequel to increased activities of alcohol dehydrogenase and pyruvate kinase, derived probably from S. cerevisiae parent. Hybrid ADH‐isozyme pattern on polyacrylamide gel corroborated the presence of S. cerevisiae ADH in the tested hybrids. Regression analyses indicated a positive correlation between ethanol production and ADH or PK or both (r ∼ 0.76–0.84).
Epizootic of Chlamydia psittaci infection in goats in Taiwan
Authors: Liao Y. K. , Chain C. Y. , Lu Y. S. , Li N. J. , Tsai H. J. , Liou P. P. 
Published: February 2007

AbstractEpizootic abortion in goats has been frequently reported in Taiwan since 1993. The outbroken flocks were found in most of districts in Taiwan. No apparent clinical signs were found in aborted doe. The typical abortion occurred in the last two months of pregnancy. The incidence of abortion was from 10% to 87% in outbroken farms in 1993, and a total of 976 out of 2130 pregnancies (46%) were found abortion in our investigation. Gross lesions in aborted fetuses included generalized haemorrhage and swollen liver. Chlamydia psittaci was isolated from tissues of aborted fetuses and from vaginal swabs of aborted does. Chlamydial antibodies were detected among 67% to 100% of aborted does from epizootic flocks. The C. psittaci was diagnosed as the causal agent in enzootic abortion. This is the first report on chlamydial isolation and antibody surveys in epizootic abortion in goats in Taiwan.
Effects of pH on the comparative culturability of fungi and bacteria from acidic and less acidic forest soils
Authors: Matthies Carola , Erhard Hans‐Peter , Drake Harold L. 
Published: February 2007

AbstractUnder aerobic conditions, the culturable microbial population of acidic forest soils was more tolerant to acidic cultivation conditions than was the culturable microbial population of less acidic soils. The number of culturable bacteria decreased sharply under acidic cultivation conditions, while the number of culturable fungi remained relatively constant over the pH range 2.2–6.5. The ratios of culturable bacteria to culturable fungi were greater than one at pH 6.5; in contrast, the bacteria‐to‐fungi ratios were less than one at pH 2.2–4. At pH's approximating those of the soils examined, culturable fungi predominated the culturable microbial community in acidic soils. However, relative to the populations resolved, acidic forest soils displayed a more acid tolerant bacterial population than did less acidic forest soils. The culturable fungal population contained both filamentous and yeast morphologies. An acid‐tolerant fungal isolate that grew at pH 1 was identified as a subspecies of Penicillium frequentans, and an acid‐tolerant yeast that grew at pH 2 was identified as the yeast stage of the basidiomycetes Ustilago maydis.
The simultaneous production of both Hly‐ and Hpm‐like hemolysins is characteristic of the Proteus penneri species
Authors: Serwecinska L. , Pytlos M. , Łukomski S. , Jaworski A. , Rózalski A. 
Published: February 2007

AbstractClinical isolates of Proteus penneri were tested for the presence of genes encoding hemolytic activity. Strains possessing DNA sequences similar to the hlyCABD genes in Escherichia coli were found. Each secreted a 110 kDa protein which reacted with a specific anti‐HlyA antiserum. Southern blotting analysis revealed that the HindIII restriction fragment pattern for the hlyCABD genes of these strains was conserved. Similarly, the chromosomal location of these genes is relatively conserved based on the pattern of NotI digested DNA fragments separated by pulsed field gel electrophoresis. One strain carried an additional copy of the hlyCABD determinant which was mapped on a second NotI genomic fragment. All strains contained also chromosomally encoded sequences related to the hpmBA genes originally cloned from Proteus mirabilis. All strains produced a 166 kDa exoprotein detected in immunoblots with a specific antiserum raised against HpmA hemolysin. The hpmBA genes were located on other NotI fragments than hlyCABD genes. In contrast to the other Proteae, the simultaneus production of both hemolysins seems to be a common characteristics of Proteus penneri isolates.
A study of climatic variability of daily central england temperatures in relation to the lamb synoptic types
Authors: Sowden I. P. , Parker D. E. 
Published: February 2007

AbstractLong‐term changes of temperature and of characteristic circulation patterns over the British Isles have been studied using catalogues of daily Central England temperature and daily Lamb circulation types for 1861 to date. Most inter‐decadal temperature variability appears to have been linked with fluctuations in circulation. For given Lamb circulation types much of the observed long‐term variability of temperature appears to derive from lack of precision in the circulation classifications.
The empirical relation between sunshine and radiation and its use in estimating evaporation in North East England
Authors: Hanna L. W. , Siam N. 
Published: February 2007

AbstractThe relation between the duration of sunshine hours and radiation derived from ten years of daily records at Eskdalemuir and Cawood differs significantly from formulae in general use with the Penman formula. When used in the Penman formula with meteorological data from North East England evaporation estimates were more satisfactory than those based on commonly used formulae. While winter months showed different relations between sunshine and radiation their use in estimating evaporation made no significant difference on cumulative evaporation over a year. The regression R/RA = 0.1894‐0.624(n/N) derived from Eskdalemuir is satisfactory for use in North East England.
The North Pacific Oscillation
Authors: Rogers Jeffery C. 
Published: February 2007

AbstractA climatological study of the North Pacific Oscillation (NPO) during Januaries and winters (D‐J‐F) between 1906 and 1978 is presented. The NPO is defined in terms of opposition in sign of mean temperature anomaly between western Alaska‐eastern Siberia (as represented by the stations at Dutch Harbor and St. Paul, Alaska) and western Canada (as represented by Edmonton). The two oscillation modes, Aleutians below normal temperature (Edmonton above normal) and Aleutians above normal temperature (Edmonton below normal), are associated with variations in the strength of the zonal westerlies over the Pacific and North America which in turn result from longitudinal variations in the mean position of the Aleutian low. A westward location of the mean low. over the Sea of Okhotsk, is associated with the development of intense mean high pressure cells over western North America while zonal flow is associated with a more eastward location of the mean low over the Gulf of Alaska. Significant spatial correlations exist between the strength of the zonal component of the geostrophic wind over the Pacific Ocean and the zonal component of the polar and subtropical easterlies over the Pacific sector.The NPO modes are associated with large regional variations in air temperature and precipitation over North America, sea surface temperatures in the North Pacific, and Bering Sea ice. The NPO is found to resemble the second eigenvector of January and winter sea level pressure anomalies. In contrast to its more frequently occurring counterpart, the North Atlantic Oscillation, the NPO is not clearly associated with hemispheric mean temperature trends and its modes occur randomly with time. The two oscillations represent separate patterns of teleconnections of sea level pressure and zonal geostrophic winds over the Northern Hemisphere.
The distribution in space of local rainfall in the Namib Desert
Authors: Sharon David 
Published: February 2007

AbstractSpatial correlation analysis has been applied to Namib rainfall, in an attempt to identify possible patterns of the spatial organization of localized storms in this area. The utility of the above technique for areas with only sparse raingauge networks is explained. Results indicate that convective storms are not randomly scattered in space but, tend to form at preferred distances from each other, around 40‐50 and 80‐100 km, with no preferred locations of, or directions between, storms. Benard cells are mentioned as possibly imposing the inferred organization of convective storms in space.
The use of global circulation models in the study of the Indian monsoon
Authors: Druyan Leonard M. 
Published: February 2007

AbstractThe agricultural economy of India depends on the regularity of the summer monsoon rains although this climatic phenomenon exhibits a natural variability which often brings disaster. There exists much literature which discusses the physical mechanisms of the monsoon in its general aspects and some attention has been given to explanations of the variability of its main characteristics. Global circulation models afford an opportunity to examine the role of each of many physical components while allowing for interaction between the planetary circulation, sometimes even the oceanic circulation, and the monsoonal one over South Asia. Experiments to date have investigated the influence of Arabian Sea and Indian Ocean surface temperature anomalies, the influence of the Himalayan Mountains, of surface albedo and of the relative importance of sensible versus latent heating in maintaining the summertime regime. Armed with a greater understanding of the causes of monsoon variability, researchers will perhaps be able to begin developing techniques for seasonal forecasting.
Atmospheric circulation variations and the occurrence of extended wet and dry spells over Southern Africa
Authors: Tyson P. D. 
Published: February 2007

AbstractVariations in rainfall over southern Africa are explained in terms of variations in pressure and circulation patterns. The extended wet spells of the quasi 18‐year oscillation in rainfall that have affected the subcontinent are shown to have occurred in association with increased pressures in the region where the subtropical ridge of the first zonal standing wave in the 500‐mb surface has its expression in the southern hemisphere, in association with the eastwards displacement or weakening of the Indian Ocean high and a probable lowering of pressure over the subcontinental interior. It is further suggested that the 10‐11 year rainfall oscillation of the southern Cape may be forced by longitudinal changes in the position of the first ridge of standing wave 3 which may oscillate with a similar quasi‐periodicity.