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991.
992.
Marie GB Hansen Mette Christoffersen Line R Thuesen Morten R Petersen Anders M Bojesen 《Acta veterinaria Scandinavica》2010,52(1):3
Background
Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum are able to infect horses. However, the extend to which Danish horses are infected and seroconvert due to these two bacteria is unknown. The aim of the present study was to evaluate the seroprevalence of B. burgdorferi sensu lato and A. phagocytophilum in Danish horses.Methods
A total of 390 blood samples collected from all major regions of Denmark and with a geographical distribution corresponding to the density of the Danish horse population were analyzed. All samples were examined for the presence of antibodies against B. burgdorferi sensu lato and A. phagocytophilum by the use of the SNAP®4DX ® ELISA test.Results
Overall, 29.0% of the horses were seropositive for B. burgdorferi sensu lato whereas 22.3% were seropositive for A. phagocytophilum.Conclusions
Antibodies against B burgdorferi sensu lato and A. phagocytophilum are commonly found among Danish horses thus showing that Danish horses are frequently infected by these organisms.993.
The coccinellid beetle Anovia punica Gordon (Coleoptera: Coccinellidae: Noviini) is an important predator of the Colombian fluted scale, Crypticerya multicicatrices Kondo & Unruh (Hemiptera: Monophlebidae). In order to gather information on the biological traits of A. punica, we conducted a series of studies, including of the developmental time of each life history stage, estimation of life table parameters, and predation rates under laboratory conditions [25.1 ± 1.6°C, with 70.5 ± 7.3% RH, and natural light regime, approx. 12:12 (L:D) h]. Developmental stages of A. punica were categorized as follows: egg stage, four larval instars, prepupal instar, pupal instar, and adult. Developmental time from egg to adult emergence averaged 29.41 ± 1.85 days, and 47.6% of the eggs developed to adulthood. Female and male survival was 94.42 and 90 days, respectively. Life table parameters show that one female of A. punica is replaced by 86 females (R 0), the intrinsic growth rate (r m ) was 0.1115, the average generation time (T) was 40 days, and the doubling time (D t ) was 6.2 days. The life table parameters suggest that A. punica can be used as a potential predator of C. multicicatrices and, more importantly, provided baseline information for a mass-rearing protocol. This is the first detailed study on the biology of A. punica that reports the potential of this predator as a biological control agent for scale insects of the tribe Iceryini. 相似文献
994.
Martina Inga Kirsch Birgit Hülseweh Christoph Nacke Torsten Rülker Thomas Schirrmann Hans-Jürgen Marschall Michael Hust Stefan Dübel 《BMC biotechnology》2008,8(1):66
Background
Venezuelan equine encephalitis virus (VEEV) belongs to the Alphavirus group. Several species of this family are also pathogenic to humans and are recognized as potential agents of biological warfare and terrorism. The objective of this work was the generation of recombinant antibodies for the detection of VEEV after a potential bioterrorism assault or an natural outbreak of VEEV. 相似文献995.
Real-time Investigation of SV40 Large T-antigen Helicase Activity Using Surface Plasmon Resonance 总被引:1,自引:0,他引:1
Jason Plyler Karl Jasheway Bodin Tuesuwan Jessica Karr Jarryd S. Brennan Sean M. Kerwin Wendi M. David 《Cell biochemistry and biophysics》2009,53(1):43-52
The simian virus 40 (SV40) genome is a model system frequently employed for investigating eukaryotic replication. Large T-antigen
(T-ag) is a viral protein responsible for unwinding the SV40 genome and recruiting necessary host factors prior to replication.
In addition to duplex unwinding T-ag possesses G-quadruplex DNA helicase activity, the physiological consequence of which
is unclear. However, formation of G-quadruplex DNA structures may be involved in genome maintenance and function, and helicase
activity to resolve these structures may be necessary for efficient replication. We report the first real-time investigation
of SV40 T-ag helicase activity using surface plasmon resonance (SPR). In the presence of ATP, T-ag was observed to bind to
immobilized single-stranded DNA, forked duplex DNA, and the human telomeric foldover quadruplex DNA sequence. Inhibition of
T-ag duplex helicase activity was observable in real-time and the intramolecular quadruplex was unwound.
相似文献
Wendi M. DavidEmail: |
996.
Gunnar W. Schade Sheena J. Solomon Ebba Dellwik Kim Pilegaard Annette Ladstätter-Weissenmayer 《Biogeochemistry》2011,106(3):337-355
In-canopy mixing ratio gradients and above-canopy fluxes of several volatile organic compounds (VOCs) were measured using
a commercial proton transfer reaction mass spectrometer (PTR-MS) in a European beech (Fagus sylvatica) forest in Denmark. Fluxes of methanol were bidirectional: Emission occurred during both day and night with highest fluxes
(0.2 mg C m−2 h−1) during a warm period; deposition occurred dominantly at daytime. Confirming previous branch-level measurements on beech,
the forest’s monoterpene emissions (0–0.5 mg C m−2 h−1), and in-canopy mixing ratios showed a diurnal cycle consistent with light-dependent emissions; a result contrasting temperature-only
driven emissions of most conifer species. Also emitted was acetone, but only at ambient temperatures exceeding 20°C. Slow
deposition dominated at lower temperatures. Our in-canopy gradient measurements contrast with earlier results from tropical
and pine forest ecosystems in that they did not show this beech ecosystem to be a strong sink for oxygenated VOCs (OVOCs).
Instead, their gradients were flat and only small deposition velocities (<0.2 cm s−1) were observed to the onsite soil. However, as methanol soil uptake was consistent and possibly related to soil moisture,
more measurements are needed to evaluate its soil sink strength. In turn, as canopy scale fluxes are net fluxes with stomatal
emissions from photosynthesizing leaves potentially affecting non-stomatal oxygenated VOC uptake, only independent, controlled
laboratory experiments may be successful in separating gross fluxes. 相似文献
997.
Zhang HC Ye H Conway BR Derian CK Addo MF Kuo GH Hecker LR Croll DR Li J Westover L Xu JZ Look R Demarest KT Andrade-Gordon P Damiano BP Maryanoff BE 《Bioorganic & medicinal chemistry letters》2004,14(12):3245-3250
A novel series of acyclic 3-(7-azaindolyl)-4-(aryl/heteroaryl)maleimides was synthesized and evaluated for activity against GSK-3beta and selectivity versus PKC-betaII, as well as a broad panel of protein kinases. Compounds 14 and 17c potently inhibited GSK-3beta (IC(50)=7 and 26 nM, respectively) and exhibited excellent selectivity over PKC-betaII (325 and >385-fold, respectively). Compound 17c was also highly selective against 68 other protein kinases. In a cell-based functional assay, both 14 and 17c effectively increased glycogen synthase activity by inhibiting GSK-3beta. 相似文献
998.
Julio A. Camarero Youngeun Kwon 《International journal of peptide research and therapeutics》2008,14(4):351-357
Many experimental approaches in biology and biophysics, as well as applications in diagnosis and drug discovery, require proteins
to be immobilized on solid supports. Protein microarrays, for example, provide a high-throughput format to study biomolecular
interactions. The technique employed for protein immobilization is a key to the success of these applications. Recent biochemical
developments are allowing, for the first time, the selective and traceless immobilization of proteins generated by cell-free
systems without the need for purification and/or reconcentration prior to the immobilization step. 相似文献
999.
Background
Metagenomics has a great potential to discover previously unattainable information about microbial communities. An important prerequisite for such discoveries is to accurately estimate the composition of microbial communities. Most of prevalent homology-based approaches utilize solely the results of an alignment tool such as BLAST, limiting their estimation accuracy to high ranks of the taxonomy tree.Results
We developed a new homology-based approach called Taxonomic Analysis by Elimination and Correction (TAEC), which utilizes the similarity in the genomic sequence in addition to the result of an alignment tool. The proposed method is comprehensively tested on various simulated benchmark datasets of diverse complexity of microbial structure. Compared with other available methods designed for estimating taxonomic composition at a relatively low taxonomic rank, TAEC demonstrates greater accuracy in quantification of genomes in a given microbial sample. We also applied TAEC on two real metagenomic datasets, oral cavity dataset and Crohn’s disease dataset. Our results, while agreeing with previous findings at higher ranks of the taxonomy tree, provide accurate estimation of taxonomic compositions at the species/strain level, narrowing down which species/strains need more attention in the study of oral cavity and the Crohn’s disease.Conclusions
By taking account of the similarity in the genomic sequence TAEC outperforms other available tools in estimating taxonomic composition at a very low rank, especially when closely related species/strains exist in a metagenomic sample.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2105-15-242) contains supplementary material, which is available to authorized users. 相似文献1000.
Ling-Yan Jiang Yuan-Yuan Zhang Zhen Li Jian-Zhong Liu 《Journal of industrial microbiology & biotechnology》2013,40(10):1143-1151
The experiments presented here were based on the conclusions of our previous proteomic analysis. Increasing the availability of glutamate by overexpression of the genes encoding enzymes in the l-ornithine biosynthesis pathway upstream of glutamate and disruption of speE, which encodes spermidine synthase, improved l-ornithine production by Corynebacterium glutamicum. Production of l-ornithine requires 2 moles of NADPH per mole of l-ornithine. Thus, the effect of NADPH availability on l-ornithine production was also investigated. Expression of Clostridium acetobutylicum gapC, which encodes NADP-dependent glyceraldehyde-3-phosphate dehydrogenase, and Bacillus subtilis rocG, which encodes NAD-dependent glutamate dehydrogenase, led to an increase of l-ornithine concentration caused by greater availability of NADPH. Quantitative real-time PCR analysis demonstrates that the increased levels of NADPH resulted from the expression of the gapC or rocG gene rather than that of genes (gnd, icd, and ppnK) involved in NADPH biosynthesis. The resulting strain, C. glutamicum ΔAPRE::rocG, produced 14.84 g l?1 of l-ornithine. This strategy of overexpression of gapC and rocG will be useful for improving production of target compounds using NADPH as reducing equivalent within their synthetic pathways. 相似文献