bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on the effect of the fungicide Euparen on cellulose‐decomposing fungi in Egyptian soil
Authors: Abdel‐Kader M. I. A. , Moubasher A. H. , Abdel‐Mallek A. Y. 
Published: February 2007

AbstractEuparen when applied to the soil at three doses (0.95, 4.75 and 9.5 mg active ingredient N,N‐dimethyl‐N'‐phenyl‐(N'‐fluorodichloro‐methylthio)‐sulfamide per kg dry soil) was generally suppressive to the total count of fungi and several fungal species. Its toxicity persisted to act till after 10 weeks from treatment with the three doses, but after 15 weeks the toxicity was completely alleviated. Trichoderma spp. were the only fungal species that was recovered from soil when Euparen was incorporated into cellulose‐CZAPEKS agar medium at the three doses (4.8, 23.8 and 47.5 ppm). The decomposition of filter paper buried in Euparen‐treated soil was significantly retarded after 1 week of incubation with the high dose. On the other hand, filter paper sprayed with the fungicide at the high dose and buried in untreated soil was decomposed at a significantly lower rate than the control after all experimental periods (15 weeks) in addition to the medium dose after 5 weeks of incubation. The growth and sporulation of Trichoderma viride on filter papers placed on the surface of carbon‐free agar medium and treated with Euparen were partially increased by the low dose, not affected by the medium dose and partially inhibited by the high dose. The colonization of the other test fungi was partially inhibited or even completely eliminated by the three doses. The mycelial dry weight of Trichoderma viride was significantly increased (nearly doubled) by the medium dose and not affected by the other two doses. The mycelial dry weight and endo 1,4‐β‐D‐glucanase production of the other test fungi were toxicated at least by the higher doses.
Keratinophilic fungi of animal and bird pens in Egypt
Authors: Bagy M. M. K. , Abdel‐Mallek A. Y. , Moharram A. M. 
Published: February 2007

AbstractSamples were collected from 44 pens under animals and birds for the estimation of keratinophilic fungi using the hair‐baiting technique. Thirty‐nine species which belong to eighteen genera were recovered. Chrysosporium, Aspergillus, and Penicillium were the most frequent genera. From keratinophilic fungi, Myceliophthora anamorph of Corynascus sepedonium, Myceliophthora anamorph of Corynascus novoguinensis, Microsporum boullardii, M. gypseum, Trichophyton mentagrophytes and Arthroderma sp. were also recovered in different frequencies.
The effect of inorganic phosphate on the production of avermectin in Streptomyces avermitilis
Authors: Čurdová Eva , Jechová Vendulka , Zima Jiří , Vaněk Zdenko 
Published: February 2007

AbstractThe effect of phosphate on the production of avermectin B1a, growth and utilization of glucose in the course of cultivation of Streptomyces avermitilis on a complex and chemically defined medium has been studied. Phosphate added at the beginning of cultivation at 1–20 mmol/1 did not distinctly affect the production of secondary metabolite. From the results it follows that the biosynthesis of avermectin tolerates high concentrations of phosphate in the medium.
Biotransformation of tryptamine derivatives in mycelial cultures of Psilocybe
Authors: Gartz Jochen 
Published: February 2007

AbstractMycelial cultures of Psilocybe cubensis capable of forming psilocybin and psilocin de novo display a high capacity for hydroxylation of tryptamine derivatives at the 4‐position. A specific biotransformation of added synthetic N,N‐diethyl‐tryptamine was found. Thus high amounts of 4‐hydroxy‐N,N‐diethyltryptamine (up to 3.3%) and a minor quantity of 4‐phosphoryloxy‐N,N‐diethyltryptamine (0.01–0.8%) were isolated from fruiting bodies of Psilocybe cubensis in corresponding experiments. This is the first example of a directed biosynthesis of tryptamine substances by fungi.An effective biotransformation of N‐methyltryptamine was also demonstrated with surface cultures of Psilocybe semilanceata. Baeocystin, a possible natural precursor of psilocybin, was detected and quantified in the biomasses.No alkaloids could be found in the culture medium.
Cellular fatty acids composition of the genus Monascus
Authors: Nishikawa Jiro , Sato Yasuhiro , Kashimura Jun , Iizuka Hiroshi 
Published: February 2007

AbstractThe cellular fatty acid composition of the genus Monascus (13 spp., 2 var., 36 strains) was analyzed by gaschromatography. The fatty acid composition of all tested 36 strains shows high similarity. The major components of fatty acids are C18:1, C18:2, C16:0, C18:0, and C16:1.No strict correlation between the characteristics of the genus Monascus and the fatty acid composition could be found. However, some strains differ from the others. These results suggested that the fatty acids composition ratio could also be a powerful method for taxonomic studies. Moreover, the fatty acid compositions of all Monascus spp. were clearly different from those of Aspergillus oryzae IAM 2600, A. niger IAM 2020, Penicillium notatum IAM 7168 and Paecilomyces variotii IF0 4855.
Monovalent cation specificity of passive transport mediated by laidlomycin and 26‐deoxylaidlomycin
Authors: Gräfe U. , Reinhardt G. , Miosga N. 
Published: February 2007

AbstractThe capacity of laidlomycin (I) and the new 26‐deoxylaidlomycin (II) to facilitate passive fluxes of cations through a layer of organic solvent (CHCl3/n‐heptane) was estimated in comparison to monensin A (III). While II displayed a 10fold higher transport rate for sodium as compared to calcium, laidlomycin (I) was distinguishable by mediating approx. 100times lower conveyance of the divalent cations.
Physical maps of the streptococcal bacteriophage A25 and C1 genomes
Authors: Pomrenke Mary E. , Ferretti Joseph J. 
Published: February 2007

AbstractA physical map of the group A streptococcal bacteriophage A25 genome was constructed using data obtained from restriction enzyme digestion analysis of purified DNA. Phage A25 was 34.6 kb in size and was digested with several enzymes which generated the following number of fragments: AvaI (3), EcoRI (2), HindIII (4), HaeII (10), HindII (22), HpaI (11), and PvuII (8). Restriction enzymes BamH1, PstI, and SalI did not cleave phage A25 DNA. A physical map of the group C streptococcal phage C1 genome was also constructed. Phage C1 was 16.9 kb in size and was cleaved by the following enzymes to give the indicated number of fragments; EcoRI (8), HaeII (4), HaeIII (10), HindIII (5), HpaI (8), PvuII (3). and SalI (2). Restriction enzymes AvaI, AvaII, BamH1, EcoRV, HpaII, and PstI did not cleave phage C1 DNA.
Production of extracellular trypsin and chymotrypsin inhibitors by aStreptomycessp
Authors: Kourteva Yordanka , Angelova Blaga , Peretz Valya 
Published: February 2007

AbstractThe production of extracellular inhibitors byStreptomycessp. 1–72, specific either to trypsin (TI‐1), or to chymotrypsin (CI‐1), was investigated in relation to the cell growth and composition of the cultivation media. The biosynthesis of the inhibitors was found to be of a growth‐associated type which reached a maximum level at late exponential phase. All of the investigated carbon sources, including starch, disaccharides and monosaccharides, equally supported the production of both inhibitors, while the effect of the different nitrogen sources considerably varied, some of then being totally ineffective. The sources which mostly supported the biosynthesis of the inhibitors were tryptone (3%) for TI‐1, and peptone (3%) for CI‐1 respectively.
Keratinophilic fungi associated with rabbit claws in Egypt
Authors: Moharram A. M. , Abdel‐Gawad K. M. 
Published: February 2007

AbstractUsing the soil plate technique, thirty one species appertaining to twenty three genera were recovered from 160 samples of rabbit claws which were collected from a rabbit farm at Assiut. Of the true keratinophilic fungi Chrysosporium tropicum was the most prevalent where it colonized 56.25% of the samples.Microsporum gypseum was rarely isolated in this study. Among the non‐keratinophilic fungi Penicillium funiculosum, P.jenseni and Paecilomyces lilacinus were of low incidence (20%, 19.37% and 14.37% of the samples, respectively).
Resistance of Escherichia coli to nourseothricin (streptothricin): Reduced penetrability of the cell wall as an additional, possibly unspecific mechanism
Authors: Seltmann Guntram 
Published: February 2007

AbstractThe resistance of E. coli strains to the antibiotic nourseothricin is known to be caused by an acetyltransferase acetylating the β‐lysine chain of the antibiotic. In addition, most of the resistant strains exhibit reduced penetrability of the outer membrane, presumably caused by a reduced amount of available negative charges. This was shown using crystal violet, Congo red, or the hydrophobic antibiotic novobiocin as indicators.
Coronatine production by Pseudomonas syringae pathovars: Screening method and capacity of product formation
Authors: Völksch Beate , Bublitz Friedemann , Fritsche Wolfgang 
Published: February 2007

AbstractThe hypertrophy of potato tuber tissue caused by coronatine could be developed into a semiquantitative screening method. A correlation between coronatine concentration and hypertrophy was demonstrated. 53 strains of P. syringae pv. glycinea and 9 strains of P. syringae pv. tomato were tested for coronatine production using this method. 24 of the investigated Pseudomonas syringae pv. glycinea strains failed to produce detectable amounts of coronatine. The remaining 29 produced coronatine in various quantities. The yields of these strains differed in orders of magnitude. The strains of P. syringae pv. tomato showed an analogous behaviour.It is assumed that coronatine is a virulence factor, which is of importance for the severing of plant diseases, implicated in the establishment of the bacteria in the plant tissue.
Induction of akinete formation in Nodularia spumigena by temperature
Authors: Pandey Rakesh Kumar 
Published: February 2007

AbstractA synchronized akinete differentiation occurred within 3 days when Nodularia filaments were incubated at a higher temperature (32 ± 1 °C). Exogenous nitrogen and carbon compounds increased the akinete frequency. The cyanophycin content of akinetes was found to be nearly 6 times higher than that of exponentially growing vegetative cells. The results suggest that the akinete differentiation is induced by the rise in temperature and akinete frequency is regulated by cellular carbon and nitrogen levels.
Acetohydroxyacid synthase from Claviceps purpurea: Partial purification and characterization
Authors: Maier Walter , Luthra Rajesh , Gröger Detlef 
Published: February 2007

AbstractAn acetohydroxyacid synthase (EC 4.1.3.18) which synthesizes α‐acetolactate from pyruvate has been isolated from two different Claviceps purpurea strains. A purification of about 142‐fold was achieved by ammonium sulfate fractionation and the use of Sepharose 6B and DEAE‐Sepharose CL‐6B columns. The purified enzyme requires thiamine pyrophosphate and a divalent metal ion (Mn2 + or Mg2 +) for maximum activity but no FAD. The optimum pH is about 6.0 and the optimum temperature is 40 °C. The enzyme is not inhibited by branched‐chain amino acids neither singly nor in combination. AHAS is strongly inhibited by p‐chloromercuribenzoate and N‐ethylmaleimide. The apparent Km values for pyruvate and TPP are 1.7 × 10−2 M and 1.2 × 10−6 M, respectively.
Fungal flora of poultry feedstuff ingredients
Authors: Moharram A. M. , Abdel‐Gawad K. M. , Megalla S. E. , Mahmoud A.‐L. E. 
Published: February 2007

AbstractOne hundred and ten samples representing five types of poultry feed ingredients were mycologically examined. These samples included soybean meal, ground maize, cotton‐seed cake, wheat bran and fish meal (22 samples each). Among the 73 mesophilic fungal species, Aspergillus flavus, A. niger and A. fumigatus were the most dominant. A. terreus, A. flavipes, Mucor circinelloides, Scopulariopsis brevicaulis, Penicillium chrysogenum, Fusarium moniliforme and Rhizopus stolonifer were found to be common on a particular ingredient and less common on the remainders. Of the twelve thermophilic and thermotolerant species, A. fumigatus, Thermomyces lanuginosus, Rhizomucor pusillus and Thermoascus thermophilus prevailed on one or more type of the different ingredients. Marked variations were observed in the rancid fatty compounds of the different samples and the values ranged between 0.663 and 3.900 mg malonaldehyde per kg sample.
Comparaison du mode d'infection et du développement des nodosités racinaires et caulinaires chez quelques légumineuses des genres Sesbania et Aeschynomene
Authors: Ramaroson Esthel , Schramm Michael 
Published: February 2007

AbstractSesbania rostrata and fifteen species of Aeschynomene are tropical legumes which can grow in flooded soils because they have both root and stem nodulation. They are of particular agronomic interest because of their potential for maintaining soil fertility. Three genera of rhizobia are associated symbiotically with these stem nodulating legumes: Rhizobium infects S. rostrata and some Aeschynomene species; Azorhizobium is specific to S. rostrata and can live outside the plant; Bradyrhizobium infects only Aeschynomene species.In S. rostrata root infection occurs by root hair curling, whereas stem nodulation is achieved by entry of bacteria at the site of emerging adventitious rootlets. Many studies have reported that infection by thread formation is observed on both roots and stems of S. rostrata.In S. rostrata, the process of root infection has been shown to follow several stages: recognition and attachment of rhizobia to the root surfaces induction of root hair curling; formation of infection threads that guide bacteria to the adjacent cortical root cells; release of bacteria into the cytoplasm of host cells where they are enveloped by host plasmalemm.Stem infection of S. rostrata has been shown to have four stages: rhizobial penetration in degenerated cortical cells through cracks at the site of emerging rootlets; Rhizobium proliferates in the intercellular cavities and initiates meristematic nodules; infection threads form in the intercellular cavities and in the host cells; rhizobia are intercellularly released by an endocytotic process.Most of the stem nodulated Aeschynomene spp. have displayed the same process of root infection as S. rostrata. A.indica is an exception in that it appears that the path of infection is constituted by the rupture of tissue restricted to the place of rootlet emergence. No infection thread formation is observed in A. indica.The unique characteristic of all stem‐nodulating legumes is the presence of pre‐determined nodulation sites on their stems. In Aeschynomene, the process of stem infection does not involve formation of infection threads but is effected by penetration of Rhizobinum through cracks which surround the root primordia. This penetration is followed by hydrolysis of host epidermic cell walls causing the release of the bacteria into cell cytoplasm.Stem‐nodulating legumes infection depends on both ecological and intrinsic legumes factors.It is important to note that the nitrogen fixation of S. rostrata. A. afraspera, and A. scabra was not inhibited by mineral nitrogen.The role of leaghemoglobin in the regulation and protection of nitrogenase activity is well established. Recently, it was suggested that superoxide dismutase. which is present at high levels in bacteroides isolated from root and stem nodules of a few stem‐nodulating legumes, would be another regulator and protector of the process of nitrogen fixation.
Interferonsensitivität verschiedener Zellkulturen: Untersuchungen zur Abhängigkeit der relativen antiviralen Aktivität vom Interferon‐Subtyp
Authors: Tonew Marion , Glück Brigitte , Ohme Elke , Wondraczek R. H. 
Published: February 2007

AbstractThe phenomenon that rHuIFN‐αl(D) displays an apparently higher antiviral activity when assayed on bovine cells as compared to human cell lines was applied to the elucidation of the nature of recombinant HuIFN prepared in our institute.These investigations were carried out by using a microtitre test, which defines biological activity as the IFN concentration leading to 50 % inhibition of the cytopathic effect of vesicular stomatitis virus (VSV). In addition, the ability of IFN to diminish the reproduction of infectious viruses was monitored. The two methods yielded similar results. With bovine cells, antiviral activities of the same order of magnitude were observed, regardless of the interferon types applied, i.e. rHuIFN‐αl. rHuIFN‐α2 and human leukocyte interferon. On human fibroblasts, however, rHuIFN‐αl had an apparently 45 to 165 times lower activity than the other two interferons. On human WISH cells, the differences in apparent activity between the respective IFNs were even greater, with factors of up to 212 fold being observed.Still more distinctive were the effects on murine L 929 cells where an antiviral effect could be confirmed only for rHuIFN‐αl whereas the other two interferons proved completely inactive.
Biochemical aspects of the resistance to nourseothricin (streptothricin) of Escherichia coli strains
Authors: Seltmann Guntram 
Published: February 2007

AbstractIn most cases Escherichia coli strains phenotypically resistant against nourseothricin (streptothricin) harbour a plasmid which codes for an acetyltransferase. This enzyme transfers an acetyl group from acetyl‐coenzyme A to an amino group of the β‐lysine (peptide) chain of the antibiotic, thus inactivating it. Additionally, the penetrability for nourseothricin of the cell wall is drastically reduced in a high percentage of the resistant strains. Both resistance mechanisms seem to be independent of each other.
Microbial biomass protein and polysaccharide production from vegetable processing wastes
Authors: Jwanny Etidal W. , Rashad Mona M. , Moharib Sorial A. 
Published: February 2007

AbstractPichia pinus was grown in flasks on extract of mango peel medium. The yield was about 2.5 g of dry yeast cells per liter. The reducing sugar concentration of the medium decreased during the fermentation from a level of about 1.5 to 0.7 gl−1 after 4 days of growth. The value of biomass production after 48 h fermentation was 3 g/g of reducing sugar in the extract of mango peel. The yeast cells contained 66.5 % crude protein. Reasonable amounts of essential amino acids could be estimated. Extracellular polysaccharides formed during fermentation were estimated. The maximum amount found was about 4.8‐5 gl−1 on the 4th day of growth. Chromatographic analysis of the purified polysaccharide hydrolysates revealed the presence of glucose, galactose, arabinose, xylose and an unknown spot near the starting point. The sugar components of exopolysaccharides hydrolysate differed during growing time.
Septation behaviour of the apical cell in Streptomyces granaticolor mycelia
Authors: Kretschmer S. 
Published: February 2007

AbstractThe septation behaviour of the apical hyphal cell, which solely brings about hyphal elongation, was studied using mycelia grown at different specific growth rates (μ) (chemostat and batch cultures). After cell wall staining it was found that both the apical cell (c1) and the adjacent subapical cell (c2) were generally unbranched. Thus, their length (L) could be easily determined.As the growth rate decreased, Lc1 as well as Lc2 decreased, but cells smaller than 5 μm were not observed, even at extremely slow rates of growth (μ = 0.06 h−1). The largest cells were observed in rich media, where Lc1 attained 4l μm.Since Lc2 represented the length of one of the new‐born daughter cells of c1, the distribution curves of Lc2 were used to look for regularity of septation. Especially at slow rates of growth, the curves indicated that in c1 septation did not occur randomly. By using Lc2 the interdivision time T of c1 was calculated. At fast rates of growth it was identical to the earlier determined replication time C, indicating that in mature hyphae septation was coupled to the rounds of DNA replication.Lc1 and Lc2 were used to calculate the length of c1 at birth and at the start of septation. It was found that upon septation the appearing daughter cells were differently sized. Depending on the growth rate, the apically situated daughter cell was 1.37 to 1.81 times larger than the subapical daughter (c2). Based on the functional heterogeneity of the sister cells a hypothesis was invented, which could explain the asymmetric septation pattern. It involves the existence of a period S between the determination of the septum site at median position and the actual process of septum formation. The duration of S was calculated, and its correlation to the T and C values at the corresponding growth rates was discussed. Two mechanisms could be distinguished, which were responsible for the immense increase of Lc1 at fast rates of growth.
Characterization of new resistance plasmids belonging to incompatibility group IncQ
Authors: Tietze Erhard , Tschäpe Helmut , Voigt Wolfgang 
Published: February 2007

AbstractNew IncQ R plasmids, pIE639 and pIE723, are characterized and compared to the prototype IncQ plasmid RSF1010. Additional resistance determinants not common on other R plasmids are located on small stretches of DNA interspacing essential regions at different positions in an otherwise unchanged core of IncQ plasmid DNA. The contribution of IncQ plasmids to resistance evolution in bacteria is discussed.
Characterization of yeasts with high L[+]‐lactic acid production: Lactic acid specific soft‐agar overlay (LASSO) and TAFE‐patterns
Authors: Witte V. , Krohn U. , Emeis C. C. 
Published: February 2007

AbstractOnly few yeast strains are known for the high level production of L[+]‐lactate. We report indications for the conspecifity of Kluyveromyces thermotolerans (formerly Saccharomyces veronae) strain CBS 4728 with Stamm 42 (formerly Saccharomyces pretoriensis, RADLER 1984). We suggest that Stamm 42 has little, if any relationships to Saccharomyces cerevisiae.Furthermore, we have optimized the method of SUBDEN et al. (1982) for the detection of lactate producing microorganisms. Using this method in a screening with 100 yeast strains of our institute collection, we could not find additional strains with high L[+]‐lactate production. This method may provide a useful tool for the molecular cloning of the unique yeast L[+]‐LDH1) gene (s).
Survey of keratinophilic and saprobic fungi in the clovenhooves and horns of goats and sheep from Egypt
Authors: Abdel‐Hafez A. I. I. , Moharram A. M. , Abdel‐Gawad K. M. 
Published: February 2007

AbstractSeventy‐six species belonging to 29 genera were collected from 320 samples of cloven‐hooves and horns of goats and sheep.Chrysosporiumwas the most common genus on the various substrates and comprehended the following species:C. asperatum, Chrysosporiumanamorph ofArthroderma cuniculi, Chrysosporiumanamorph ofAnthroderma curreyi, C. georgii, C. indicum, C. keratinophilum, C. lobatum, C. lucknowense, C. pannicola, C. pseudomerdarium, C. queenslandicum, Chrysosporiumstate ofThielavia sepedoniumandC. tropicum.Some interesting fungi were isolated:Myceliophthoraanamorph ofArthroderma tuberculatum, Myceliophthoraanamorph ofCorynoascus novoguineensis, Myceliophthoraanamorph ofCtenomyces serratus, Trichosporon cutaneum, Trichophyton terrestreandT. verrucosum.Also, several saprobic filamentous fungi tolerating high levels of cycloheximide were islolated of which numerous members ofAcremonium, Aspergillus, Chaetomium, Fusarium, Penicillium, Scopulariopsisand serveral others.