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541.
542.
The binding of the intermediate proteins φ1 and φ3 from the mussel Mytilus edulis to DNA was studied in comparison with the typical protamine from the squid Loligo vuigaris using precipitation curves, thermal denaturation and X-ray diffraction techniques. The properties of protein φ1 appear to be very close to those of typical protamines while the properties of protein φ3 are notably different. The method of reconstitution influences the structural properties of the complexes. This effect is most pronounced in the case of protein φ3. The structural heterogeneity of the protein component in the complexes is discussed in the light of these observations. 相似文献
543.
Elena Marco‐Herrero Asvin P. Torres José A. Cuesta Guillermo Guerao Ferran Palero Pere Abelló 《Zoologica scripta》2013,42(4):427-439
The complete larval series (zoea I, zoea II and megalopa) of the crab Ergasticus clouei is described and illustrated based on plankton samples from Mediterranean waters. The zoea II and megalopal stages, previously unknown, are described here for the first time. Nucleotide sequence analysis of two gene regions (16S rDNA and Cox1 genes) confirmed the assignment of these larvae to Ergasticus clouei. The molecular analyses and the morphology of the larval stages revealed large differences between Ergasticus and Inachus, the type genus of the family Inachidae. In fact, E. clouei larvae presented a series of morphological characters, such as antennal shape and mouthparts setation pattern that placed them closer to the family Oregoniidae. The phylogenetic analyses also showed significant support for the monophyly of the Oregoniidae + Ergasticus group. The data argue for removal of Ergasticus and the related genera (Bothromaia, Pleisticanthoides, Parapleisticantha and Pleistacantha) from the Inachidae and their placement within the Oregoniidae as a separate subfamily, Pleistacanthinae ?tev?i?, 2005. Our results demonstrate that larval stages provide reliable morphological traits, independent from those of adults, to help resolving relationships among Majoidea genera. 相似文献
544.
Pere Mir-Artigues Richard M. Twyman Derry Alvarez Pedro Cerda Bennasser Merce Balcells Paul Christou Teresa Capell 《Biotechnology and bioengineering》2019,116(10):2526-2539
By the end of 2017, the Food and Drug Administration had approved a total of 77 therapeutic monoclonal antibodies (mAbs), most of which are still manufactured today. Furthermore, global sales of mAbs topped $90 billion in 2017 and are projected to reach $125 billion by 2020. The mAbs approved for human therapy are mostly produced using Chinese hamster ovary (CHO) cells, which require expensive infrastructure for production and purification. Molecular pharming in plants is an alternative approach with the benefits of lower costs, greater scalability, and intrinsic safety. For some platforms, the production cycle is also much quicker. But do these advantages really stack up in economic terms? Earlier techno-economic evaluations have focused on specific platforms or processes and have used different methods, making direct comparisons challenging and the overall benefits of molecular pharming difficult to gauge. Here, we present a simplified techno-economic model for the manufacturing of mAbs, which can be applied to any production platform by focusing on the most important factors that determine the efficiency and cost of bulk drug manufacturing. This model develops economic concepts to identify variables that can be used to achieve cost savings by simultaneously modeling the dynamic costs of upstream production at different scales and the corresponding downstream processing costs for different manufacturing modes (sequential, serial, and continuous). The use of simplified models will help to achieve meaningful comparisons between diverse manufacturing technologies. 相似文献
545.
Pere Pons Josep Maria Bas David Estany-Tigerström 《Biodiversity and Conservation》2010,19(6):1711-1723
Cork oak forests invaded by the Argentine ant Linepithema humile have a lower abundance and biomass of arthropod prey for birds than uninvaded forests. We studied whether the biomass of
breeding insectivorous birds was also lower in invaded areas. We explored this and other possible effects of the ant invasion
on the bird community by censusing birds in transects located in four invaded and four uninvaded forest sites in Catalonia
(NE Spain) for 3 years. Redundancy analysis showed only slight differences in the community composition between forests. Two
insectivorous species, Luscinia megarhynchos and Fringilla coelebs, tended to be less abundant in invaded areas although two others, Phylloscopus bonelli and Sylvia melanocephala, showed the opposite trend. Overall, the differences in prey biomass between invaded and uninvaded areas did not entail a
biomass shift in the guild of insectivorous birds, regardless of whether they were shrub or canopy foragers. The main role
of the habitat structure in determining bird densities and food resources being non-limiting in the studied forests are two
possible non-exclusive explanations for this inconsistency. At today’s levels, the Argentine ant invasion does not appear
to have greatly determined the insectivorous bird assemblage of the forests evaluated. 相似文献
546.
Construction of a reference linkage map of Vitis amurensis and genetic mapping of Rpv8, a locus conferring resistance to grapevine downy mildew 总被引:1,自引:0,他引:1
Blasi P Blanc S Wiedemann-Merdinoglu S Prado E Rühl EH Mestre P Merdinoglu D 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,123(1):43-53
Downy mildew, caused by the oomycete Plasmopara viticola, is one of the major threats to grapevine. All traditional cultivars of grapevine (Vitis vinifera) are susceptible to downy mildew, the control of which requires regular application of fungicides. In contrast, many sources of resistance to P. viticola have been described in the Vitis wild species, among which is V. amurensis Rupr. (Vitaceae), a species originating from East Asia. A genetic linkage map of V. amurensis, based on 122 simple sequence repeat and 6 resistance gene analogue markers, was established using S1 progeny. This map covers 975?cM on 19 linkage groups, which represent 82% of the physical coverage of the V. vinifera reference genetic map. To measure the general level of resistance, the sporulation of P. viticola and the necrosis produced in response to infection, five quantitative and semi-quantitative parameters were scored 6?days post-inoculation on the S1 progeny. A quantitative trait locus (QTL) analysis allowed us to identify on linkage group 14 a major QTL controlling the resistance to downy mildew found in V. amurensis, which explained up to 86.3% of the total phenotypic variance. This QTL was named ??Resistance to Plasmopara viticola 8?? (Rpv8). 相似文献
547.
548.
Differential acetylation of core histones in rat cerebral cortex neurons during development and aging 总被引:1,自引:0,他引:1
Core histones can be modified by aceylation and this modification has been correlated with the modulation of chromatin condensation and histone deposition. We have now studied the levels of acetylation of the core histones in rat brain cortical neurons from the middle of the period of neuronal proliferation through postnatal development and aging. The results show that the level of acetylation of H4 decreases with age. The kinetics of H4 deacetylation show a perinatal fast phase followed by a much slower phase that spans the rest of the period examined. H4 deacetylation is accounted for by the decrease of the monoacetylated species, the proportions of the more highly acetylated species remaining essentially constant. By contrast to histone H4, the overall levels of acetylation and the proportions of the different acetylated species of H2A, H2B and H3 remain unchanged throughout the period examined. Furthermore, the variants belonging to a given histone class always show the same level of acetylation. The fact that in neurons the level of monoacetylated H4 decreases during development and aging, in sharp contrast with the constancy of the levels of all other acetylated histone species, raises the possibility that in interphase chromatin monoacetylated H4 may have a central role in the modulation of chromatin structure. The results also suggest that the slow decrease of the proportion of monoacetylated H4 may imply a gradual loss of chromatin structural plasticity and thus lead to aging. 相似文献
549.
The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession numbers L06866-L06893. 相似文献