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排序方式: 共有217条查询结果,搜索用时 15 毫秒
1.
Madritsch Silvia Bomers Svenja Posekany Alexandra Burg Agnes Birke Rebekka Emerstorfer Florian Turetschek Reinhard Otte Sandra Eigner Herbert Sehr Eva M. 《Plant molecular biology》2020,104(4-5):379-380
Plant Molecular Biology - In the above mentioned publication, part of Fig. 6B was distorted (extra diagonal lines appeared). The original article has been corrected and the proper version... 相似文献
2.
Albert L. Harting Michelle M. Barbieri Jason D. Baker Tracy A. Mercer Thea C. Johanos Stacie J. Robinson Charles L. Littnan Katie M. Colegrove Dave S. Rotstein 《Marine Mammal Science》2021,37(1):235-250
Identifying, assessing, and ranking the impact of individual threats is fundamental to the conservation and recovery of rare and endangered species. In this analysis, we quantify not only the frequency of specific causes-of-death (CODs) among Main Hawaiian Island (MHI) monk seals, but also assess the impact of individual CODs on the intrinsic growth rate, λ, of the MHI population. We used gross necropsy results, histopathology, and other evidence to assign probabilities of 11 COD types to each mortality and then used Monte Carlo sampling to evaluate the influence of each COD on λ. By right censoring realizations involving specific CODs, we were able to estimate λ (and its associated uncertainty) when CODs were selectively removed from influencing survival. Applying the analysis to all known and inferred deaths believed to have occurred 2004–2019, the CODs with the largest influence on λ were anthropogenic trauma, anthropogenic drowning, and protozoal disease. In aggregate, anthropogenic CODs had a larger effect on the growth rate than either natural or disease CODs. Possible bias associated with differential carcass detection, recovery, and COD classification are discussed. 相似文献
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4.
Seminatural grasslands provide habitats for various species and are important for biodiversity conservation. The understanding of the diverse responses of species and traits to different grassland managenient methods is therefore urgently needed. We disentangled the role of grassland management (fertilization and irrigation), vegetation structure (biomass, sward height) and plant quality (protein and fiber content) for Orthoptera communities in lowland hay meadows in Germany. We found vegetation structure to be the most important environmental category in explaining community structure of Orthoptera (species richness, total individuals, fiinctional diversity and species composition). Intensively used meadows (fertilized, irrigated, high plant biomass) were characterized by assemblages with few species, low functional diversity, and low conservation value. Thereby, the relatively moderate fertilizer inputs in our study system of up to -75 kg N/ha/year reduced functional diversity of Orthoptera, while this negative effect of fertilization was not detectable when solely considering taxonomic aspects. We found strong support for a prominent role of plant quality in shaping Orthoptera communities and especially the trait composition. Our findings demonstrate the usefulness of considering both taxonomic and functional comp on ents (functio nal diversity) in biodiversity research and we suggest a stronger involvement of plant quality measures in Orthoptera studies. 相似文献
5.
Knox OG Killham K Artz RR Mullins C Wilson M 《Applied and environmental microbiology》2004,70(8):4666-4671
There is much interest in the use of seed-applied bacteria for biocontrol and biofertilization, and several commercial products are available. However, many attempts to use this strategy fail because the seed-applied bacteria do not colonize the rhizosphere. Mechanisms of rhizosphere colonization may involve active bacterial movement or passive transport by percolating water or plant roots. Transport by other soil biota is likely to occur, but this area has not been well studied. We hypothesized that interactions with soil nematodes may enhance colonization. To test this hypothesis, a series of microcosm experiments was carried out using two contrasting soils maintained under well-defined physical conditions where transport by mass water flow could not occur. Seed-applied Pseudomonas fluorescens SBW25 was capable of rhizosphere colonization at matric potentials of -10 and -40 kPa in soil without nematodes, but colonization levels were substantially increased by the presence of nematodes. Our results suggest that nematodes can have an important role in rhizosphere colonization by bacteria in soil. 相似文献
6.
Sørensen BK Højrup P Østergård E Jørgensen CS Enghild J Ryder LR Houen G 《Analytical biochemistry》2002,304(1):33-41
A fast and convenient method for silver staining of proteins on electroblotting membranes was developed based on Gallyas' histochemical intensifier and applied to human endothelial cell proteins separated by one- and two-dimensional electrophoresis and electroblotted to polyvinyl difluoride membranes. The method allowed detection of proteins on membranes with a sensitivity equal to the sensitivity of the most sensitive silver-staining protocols for electrophoresis gels. Also, the method was compatible with preceding immunostaining on the same membrane. Furthermore, an intensifying method for proteins in silver-stained SDS-PAGE gels was developed based on Gallyas' histochemical intensifier. This method was applied to proteins separated by one- and two-dimensional gel electrophoresis and visualized by one of several silver-staining methods. Maximal intensification was achieved for the less sensitive but fast acidic silver-staining protocols, but even for the very sensitive alkaline protocols a significant increase in signal to noise ratio was obtained. In particular, negatively stained or invisible proteins on the silver-stained gels were found to be visualized by the Gallyas stain. Proteins from silver-stained and Gallyas-stained gels were identified by mass spectrometry, and the intensification procedure was fully compatible with mass spectrometry. 相似文献
7.
Rebekka Sontowski Detlef Bernhard Christoph Bleidorn Martin Schlegel Michael Gerth 《Ecology and evolution》2015,5(19):4345-4353
Wolbachia (Alphaproteobacteria) is an inherited endosymbiont of arthropods and filarial nematodes and was reported to be widespread across insect taxa. While Wolbachia's effects on host biology are not understood from most of these hosts, known Wolbachia‐induced phenotypes cover a spectrum from obligate beneficial mutualism to reproductive manipulations and pathogenicity. Interestingly, data on Wolbachia within the most species‐rich order of arthropods, the Coleoptera (beetles), are scarce. Therefore, we screened 128 species from seven beetle families (Buprestidae, Hydraenidae, Dytiscidae, Hydrophilidae, Gyrinidae, Haliplidae, and Noteridae) for the presence of Wolbachia. Our data show that, contrary to previous estimations, Wolbachia frequencies in beetles (31% overall) are comparable to the ones in other insects. In addition, we used Wolbachia MLST data and host phylogeny to explore the evolutionary history of Wolbachia strains from Hydraenidae, an aquatic lineage of beetles. Our data suggest that Wolbachia from Hydraenidae might be largely host genus specific and that Wolbachia strain phylogeny is not independent to that of its hosts. As this contrasts with most terrestrial Wolbachia–arthropod systems, one potential conclusion is that aquatic lifestyle of hosts may result in Wolbachia distribution patterns distinct from those of terrestrial hosts. Our data thus provide both insights into Wolbachia distribution among beetles in general and a first glimpse of Wolbachia distribution patterns among aquatic host lineages. 相似文献
8.
Protein function is considerably altered by posttranslational modification. In recent years, cycles of acetylation/deacetylation emerged as fundamental regulators adjusting biological activity of many proteins. Particularly, protein deacetylation by Sirtuins, a family of atypical histone deacetylases (HDACs), was demonstrated to regulate fundamental cell biological processes including gene expression, genome stability, mitosis, nutrient metabolism, aging, mitochondrial function and cell motility. Given this wealth of biological functions, perhaps not unexpectedly then, pharmacological compounds targeting Sirtuin activity are now prime therapeutic agents for alleviating severity of major diseases encompassing diabetes, cancer, cardiovascular and neurodegenerative disorders in many organs. In this review, we will focus on the brain and its physiological and pathological processes governed by Sirtuin-mediated deacetylation. Besides discussing Sirtuin function in neurodegenerative diseases, emphasis will be given on the mounting evidence deciphering key developmental brain functions for Sirtuins in neuronal motility, neuroprotection and oligodendrocyte differentiation. In this respect, we will particularly highlight functions of the unconventional family member SIRT2 in post-mitotic neurons and glial cells. 相似文献
9.
<Emphasis Type="Italic">Bacillus megaterium</Emphasis>—from simple soil bacterium to industrial protein production host 总被引:2,自引:0,他引:2
Vary PS Biedendieck R Fuerch T Meinhardt F Rohde M Deckwer WD Jahn D 《Applied microbiology and biotechnology》2007,76(5):957-967
Bacillus megaterium has been industrially employed for more than 50 years, as it possesses some very useful and unusual enzymes and a high capacity
for the production of exoenzymes. It is also a desirable cloning host for the production of intact proteins, as it does not
possess external alkaline proteases and can stably maintain a variety of plasmid vectors. Genetic tools for this species include
transducing phages and several hundred mutants covering the processes of biosynthesis, catabolism, division, sporulation,
germination, antibiotic resistance, and recombination. The seven plasmids of B. megaterium strain QM B1551 contain several unusual metabolic genes that may be useful in bioremediation. Recently, several recombinant
shuttle vectors carrying different strong inducible promoters and various combinations of affinity tags for simple protein
purification have been constructed. Leader sequences-mediated export of affinity-tagged proteins into the growth medium was
made possible. These plasmids are commercially available. For a broader application of B. megaterium in industry, sporulation and protease-deficient as well as UV-sensitive mutants were constructed. The genome sequence of
two different strains, plasmidless DSM319 and QM B1551 carrying seven natural plasmids, is now available. These sequences
allow for a systems biotechnology optimization of the production host B. megaterium. Altogether, a “toolbox” of hundreds of genetically characterized strains, genetic methods, vectors, hosts, and genomic sequences
make B. megaterium an ideal organism for industrial, environmental, and experimental applications. 相似文献
10.
Biedendieck R Beine R Gamer M Jordan E Buchholz K Seibel J Dijkhuizen L Malten M Jahn D 《Applied microbiology and biotechnology》2007,74(5):1062-1073
Fructosyltransferases, like the Lactobacillus reteri levansucrase, are important for the production of new fructosyloligosaccharides. Various His6- and Strep-tagged variants of this enzyme were recombinantly produced and exported into the growth medium using the Gram-positive
bacterium Bacillus megaterium. Nutrient-rich growth medium significantly enhanced levansucrase production and export. The B. megaterium signal peptide of the extracellular esterase LipA mediated better levansucrase export compared to the one of the penicillin
amidase Pac. The combination of protein export via the LipA signal peptide with the coexpression of the signal peptidase gene
sipM further increased the levansucrase secretion. Fused affinity tags allowed the efficient one-step purification of the recombinant
proteins from the growth medium. However, fused peptide tags led to slightly decreased secretion of tested fusion proteins.
After upscaling 2 to 3 mg affinity tagged levansucrase per liter culture medium was produced and exported. Up to 1 mg of His6-tagged and 0.7 mg of Strep-tagged levansucrase per liter were recovered by affinity chromatography. Finally, the purified
levansucrase was shown to synthesize new fructosyloligosaccharides from the novel donor substrates d-Gal-Fru, d-Xyl-Fru, d-Man-Fru, and d-Fuc-Fru.
R. Biedendieck and R. Beine contributed equally to this work. 相似文献