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Earlier research demonstrated the secretion of benzoate, which must be oxygenated to its 4-hydroxy derivative in order to be included in further sulfate uptake processes. The present study on Desulfotomaculum acetoxidans DSM 771 was designed to determine the activity and catalytic specificity of the enzyme (most probably peroxidase) catalyzing the hydroxylation of secreted benzoate. Peroxidase activity measured with ABTS (2,2'-azino-bis (3-ethylbenzathiazoline-6-sulfonic acid) during cultivation indicated the greatest activity on the third and thirteen days (3.4 and 2.3 nkat per ml sample respectively). The highest (0.7979) correlation coefficient was calculated between peroxidase activity and hydrogen peroxide levels. The cell walls from 3- and 13-day cultures were subjected to an isolation procedure, PIPES (piperazine-N,N'-bis (2-ethane-sulfonic acid) extract followed by preparative electrophoresis. The extracts of a~30 kDa band on the gel were analyzed by Western blotting and the membrane was stained with TMB (3,3',5,5'-tetramethylbenzidine-specific for the presence of peroxidase). This same protein was incubated for 6 h with benzoate, H₂O₂ Na₂SO₄. The product formed a complex with Fe³⁺ whose maximum absorption spectra (501.7 nm) corresponded with a ferric complex of synthetic 4-hydroxy-3-sulfo-benzoate. The H₂S level during the cultivation was higher in culture grown with 15.5 mM 4-hydroxy-3-sulfo-benzoate than in culture with lactate supplemented with 15.5 mM sulfate. The role of peroxidase in oxygen utilization and sulfate uptake is discussed.
The study concludes the results of research conducted for over 20 years in Spitsbergen by the Department of Soil Science of the Maria Curie-Skłodowska University. The results have been presented in nine figures provided with concise commentaries and in the form of seven conclusions.
High-resolution melting analysis (HRMA) was used to screen potential SNPs in the exons of chicken CAPN1 (μ-calpain/large subunit) gene. A total of 312 DNA samples from Beijing-you chickens were used for detection. Twelve pairs of primer were designed to amplify twelve different exons and SNPs were detected in five of them. HRMA was also compared with PCR-SSCP analysis for genotyping of a known SNP site in the chicken adipocyte fatty acid binding protein gene (A-FABP). Amplicons of 275-bp fragment, bracketing the polymorphic site, were grouped by PCR-SSCP into three genotypem designated as CC, TT and CT. Small amplicons (56 bp) within the 275-bp fragments were designed to maximize the Tm difference between homozygotes and to genotype all possible three genotypes after a single melting analysis successfully. Results from different methods were cross-validated and sequencing results from randomly selected heterozygotes and homozygotes confirmed the specificity of HRM technique. The full consistency proved that HRMA was a useful tool for rapid, close-tube genotyping of polymorphic sites. It has great potential for SNPs detection and scanning especially on a large scale.
Bony fishes (Teleostei) play an important role in the completion of life cycles of helminth parasites in the Antarctica. These fishes may be definitive, second intermediate or paratenic hosts of the helminths. The most species-rich taxon is Digenea. Virtually all of these digeneans use teleosts as definitive hosts. Only one species, Otodistomum cestoides, occurs as the adult stage in skates (Chondrichthyes), with teleosts as its second intermediate host. Among 14 cestode species maturing in fishes only one, Parabothriocephalus johnstoni, occurs in a bony fish, Macrourus whitsoni, whereas the others are parasites of Chondrichthyes (cartilaginous fishes). Antarctic Chondrichthyes are not infected with nematode and acanthocephalan species. Specificity to the intermediate and/or paratenic hosts of the majority of Antarctic helminths is wide, whereas that for definitive hosts is often narrower, restricted to one order or sometimes even to one or two host species. Almost all of 73 helminth species maturing in Antarctic fishes are endemics. Only 4 digenean and one nematode species are cosmopolitan or bipolar.
Along to alarm calls, Eurasian ground squirrels of the genus Spermophilus also produce other call types toward potential predators and rival conspecifics. Individually identified 50 speckled (Spermophilus suslicus), 18 European (S. citellus) and 59 yellow (S. fulvus) ground squirrels were examined for interspecies differences in their vocal repertoires. A separate sample of 116 (90 adult and 26 juvenile) S. suslicus was examined for presence of ultrasound in their alarm calls. In addition, all tonal calls in all the three species were checked for presence of nonlinear phenomena. Calls were elicited by approaching animals in live-traps or near burrows; some types of vocalizations were also recorded during handling. Eight call types, three tonal and five wideband ones, were described. Vocal repertoires were remarkably similar between species, excluding the alarm calls, which were species-specific. Alarm calls with ultrasonic components were found in two individuals of S. suslicus. Concerning nonlinear phenomena, biphonation in alarm calls of S. suslicus, frequency jumps and sidebands in screams of S. citellus, frequency jumps and subharmonics in screams of S. fulvus were found. Results are discussed with literature evidence on audible and ultrasonic vocalizations in ground squirrels.
Nanodiagonastic methods in plant pathology are used for enhancing detection and identification of different plant pathogens and toxigenic fungi. Improvement of the specificity and efficiency of the polymerase chain reaction (PCR) by using some nanoparticles is emerging as a new area of research. In the current research, silver, zinc, and gold nanoparticles were used to increase the yield of DNA for two plant pathogenic fungi including soil-borne fungus Rhizoctonia solani and toxigenic fungus Alternaria alternata. Gold nanoparticles combined with zinc and silver nanoparticles enhanced both DNA yield and PCR products compared to DNA extraction methods with ALB buffer, sodium dodecyl sulfate, ALBfree from protinase K, ZnNPs and AgNPs. Also, by using ZnNPs and AgNPs the DNA yield was enhanced and the sensitivity of random amplified polymorphic DNA (RAPD) PCR products was increased. Application of nanomaterials in the PCR reaction could increase or decrease the PCR product according to the type of applied nanometal and the type of DNA template. Additions of AuNPs to PCR mix increased both sensitivity and specificity for PCR products of the tested fungi. Thus, the use of these highly stable, commercially available and inexpensive inorganic nano reagents open new opportunities for improving the specificity and sensitivity of PCR amplicon, which is the most important standard method in molecular plant pathology and mycotoxicology.
Molybdenum-containing enzymes, aldehyde oxidase and xanthine oxidase, are im­portant in the oxidation of N-heterocyclic xenobiotics. However, the role of these en­zymes in the oxidation of drug-derived aldehydes has not been established. The present investigation describes the interaction of eleven structurally related benzaldehydes with guinea pig liver aldehyde oxidase and bovine milk xanthine oxidase, since they have similar substrate specificity to human molybdenum hydroxylases. The compounds under test included mono-hydroxy and mono-methoxy benzaldehydes as well as 3,4-dihydroxy-, 3-hydroxy-4-methoxy-, 4-hydroxy-3-metho- xy-, and 3,4-dimethoxy-benzaldehydes. In addition, various amines and catechols were tested with the molybdenum hydroxylases as inhibitors of benzaldehyde oxida­tion. The kinetic constants have shown that hydroxy-, and methoxy-benzaldehydes are excellent substrates for aldehyde oxidase (Km values 5*10 M to 1^10 M) with lower affinities for xanthine oxidase (Km values around 10- M). Therefore, alde­hyde oxidase activity may be a significant factor in the oxidation of the aromatic alde­hydes generated from amines and alkyl benzenes during drug metabolism. Com­pounds with a 3-methoxy group showed relatively high Vmax values with aldehyde oxidase, whereas the presence of a 3-hydroxy group resulted in minimal Vmax values or no reaction. In addition, amines acted as weak inhibitors, whereas catechols had a more pronounced inhibitory effect on the aldehyde oxidase activity. It is therefore possible that aldehyde oxidase may be critical in the oxidation of the analogous phenylacetaldehydes derived from dopamine and noradrenaline.
In this study we present a faunistic overview of an investigation of arboreal phytophagous beetles collected from primeval forests and managed forests of Białowiea and Borecka Forests by insecticidal knock-down in 2001 and 2002. The whole dataset is based on 122 fogging samples and on stem eclector samples from 49 trees. In the area of Białowiea Forest 78 fogging samples from common oak (Quercus robur L.), 28 from spruce (Picea abies (L.) KARST.), 13 from hornbeam (Carpinus betulus L.) and 3 from different trees (Acer platanoides L., Populus tremula L., Pinus sylvestris L.) were taken. The samples from ancient woodland, primary forest sanctuaries, and different-aged managed forest stands revealed 129 phytophagous beetle species and 24458 individuals of the families Chrysomelidae, Bruchidae, Anthribidae, Rhynchitidae, Attelabidae, Apionidae, Nanophyidae, and Curculionidae. The stem eclector catches resulted in 32 species and 7077 individuals of Chrysomelidae, Anthribidae, Apionidae and Curculionidae. In the area of Borecka Forest 11 trees were fogged (3 Quercus robur L., 4 Picea abies, 3 Carpinus betulus and 1 Tilia cordata MILL.), resulting in 25 species and 1531 individuals. The following seven species,mainly collected by fogging, were previously not recorded from Białowiea forest: Zeugophora frontalis, Longitarsus curtus, Cryptocephalus nitidus, Crepidodera nitidula, Bruchidius marginalis, Acanthoscelides obtectus, and Phaeochrotes cinctus. Some rare species as Cryptocephalus querceti, Polydrusus flavipes, Anthonomus pinivorax, Magdalis fuscicornis, Magdalis exarata, Rhynchaenus pilosus, and Rhynchaenus hortorum were caught in medium or large numbers indicating that they preferably occur in the canopy. Full-winged specimens of Psylliodes cucullatus were found for the first time. Canopy communities were dominated by the feeding generalist Strophosoma capitatum (47.5% of all weevils, Anthribidae excluded) and other broad-nosed weevils of the genera Phyllobius und Polydrusus. Broad-nosed weevils represented 92.1% of the total weevil catch. Polydrusus flavipes proved to be a characteristic species of the wet oak forest, where it was abundant mainly on old oak trees. 36% of the weevil species, but only 13% of the leaf beetle species develop on the sampled trees (Quercus, Picea, and Carpinus). The remaining species develop on other forest trees (22% of the leaf beetles and 32% of the weevils), on herbs, low shrubs or in the open country (65% of the leaf beetles and 32% of the weevils); rarely sampled tree genera were not considered in this analysis.
This study presents data from a molecular survey of the species of the genus Culicoides from the region of Kalimok Field Station (NE Bulgaria) and haemosporidian parasites occurring in them in order to investigate the host-parasite specificity of haemosporidians to their dipteran vectors. The identification of Culicoides spp. was carried out by morphological and molecular-genetic methods. We collected and analysed 230 individuals of the genus Culicoides. Nine species were found. Eight species were identified morphologically; Culicoides obsoletus, C. riethi, C. newsteadi, C. circumscriptus, C. festivipennis, C. punctatus, C. pictipennis and C. puncticollis. The ninth species might be classified as either of C. nubeculosus or C. riethi and its identification needs additional investigations. The total prevalence of Haemoproteus in the examined biting midges was 2.17%. Three individuals of C. pictipennis were infected with the Haemoproteus lineage TURDUS2 (prevalence 16.67%), a common parasite of thrushes (Turdidae). Two individuals of C. circumscriptus contained Haemoproteus lineages (prevalence 2.78%); these were the lineage HAWF2 (previously reported from Coccothraustes coccothraustes) and a new lineage CULCIR1 not previously reported in the literature.
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