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951.
IRAP and REMAP assessments of genetic similarity in rice 总被引:1,自引:0,他引:1
952.
Ghelardi E Celandroni F Salvetti S Fiscarelli E Senesi S 《Microbes and infection / Institut Pasteur》2007,9(5):591-598
The occurrence of Bacillus thuringiensis bacteremia in a neutropenic patient suffering from severe pulmonary disease addressed the question of whether the aggressive behavior of B. thuringiensis depended on the host status and/or on the membrane-damaging toxins the isolate produced. After intratracheal injection, BALB/c mice developed pneumonia followed by fatal dissemination into deep organs, with mice rendered neutropenic by cyclophosphamide injection being extremely more susceptible to infection than normal animals. In animals infected with isogenic strains of B. thuringiensis progressively more defective in membrane-damaging toxins (407 Cry->IP2>MP02), an increase in the 50% lethal dose was registered (3.9x10(5), 1.1x10(6), 1.2x10(7)CFU). Consistently, after non-lethal dose application, only 407 Cry- replicated intrapulmonary, reaching a bacterial burden 4.7-fold and 40.9-fold higher than IP2 (P=0.018) and MP02 (P=0.008) at 48h post-inoculation. Notably, the time-course of infection was similar in animals infected with viable bacilli or spores, with neutropenic mice always being more susceptible to infection. The overall results indicate that B. thuringiensis may be responsible for opportunistic infections and strongly suggest that membrane-damaging toxins contribute to intrapulmonary bacterial persistence favoring dissemination. 相似文献
953.
Serra-Maluquer Xavier Gazol Antonio Sangüesa-Barreda Gabriel Sánchez-Salguero Raúl Rozas Vicente Colangelo Michele Gutiérrez Emilia Camarero J. Julio 《Ecosystems》2019,22(6):1325-1337
Ecosystems - Warming-related growth decrease on southern Fagus sylvatica forests has been observed in different regions; however, whether it is a generalized fact or not remains unclear. Here we... 相似文献
954.
Durum wheat seedling responses to simultaneous high light and salinity involve a fine reconfiguration of amino acids and carbohydrate metabolism 下载免费PDF全文
Pasqualina Woodrow Loredana F. Ciarmiello Maria Grazia Annunziata Severina Pacifico Federica Iannuzzi Antonio Mirto Luisa D'Amelia Emilia Dell'Aversana Simona Piccolella Amodio Fuggi Petronia Carillo 《Physiologia plantarum》2017,159(3):290-312
Durum wheat plants are extremely sensitive to drought and salinity during seedling and early development stages. Their responses to stresses have been extensively studied to provide new metabolic targets and improving the tolerance to adverse environments. Most of these studies have been performed in growth chambers under low light [300–350 µmol m?2 s?1 photosynthetically active radiation (PAR), LL]. However, in nature plants have to face frequent fluctuations of light intensities that often exceed their photosynthetic capacity (900–2000 µmol m?2 s?1). In this study we investigated the physiological and metabolic changes potentially involved in osmotic adjustment and antioxidant defense in durum wheat seedlings under high light (HL) and salinity. The combined application of the two stresses decreased the water potential and stomatal conductance without reducing the photosynthetic efficiency of the plants. Glycine betaine (GB) synthesis was inhibited, proline and glutamate content decreased, while γ‐aminobutyric acid (GABA), amides and minor amino acids increased. The expression level and enzymatic activities of Δ1‐pyrroline‐5‐carboxylate synthetase, asparagine synthetase and glutamate decarboxylase, as well as other enzymatic activities of nitrogen and carbon metabolism, were analyzed. Antioxidant enzymes and metabolites were also considered. The results showed that the complex interplay seen in durum wheat plants under salinity at LL was simplified: GB and antioxidants did not play a main role. On the contrary, the fine tuning of few specific primary metabolites (GABA, amides, minor amino acids and hexoses) remodeled metabolism and defense processes, playing a key role in the response to simultaneous stresses. 相似文献
955.
To gain a better understanding of the function of the yeast histone H1, its role in nucleosome positioning was studied. With
this objective in mind, we analyzed a chromatin region of the yeast Chromosome (Chr) IX, in which there are two closely packed
open reading frames (ORFs), POT1 and YIL161w. This locus shows a regular ladder of 13 stochastically positioned nucleosomes, which is unaffected by the absence of the
HHO1 gene. This suggests that histone H1 has no effect on nucleosome positioning in yeast.
Received: 30 December 1998 / Accepted: 6 May 1999 相似文献
956.
Dinesh Jaishankar Cormac Cosgrove Prathyaya Ramesh James Mahon Rohan Shivde Emilia R. Dellacecca Shiayin F. Yang Jeffrey Mosenson Jos A. Guevara-Patio I. Caroline Le Poole 《Cell stress & chaperones》2021,26(5):845
Developing immunosuppressive therapies for autoimmune diseases comes with a caveat that immunosuppression may promote the risk of developing other conditions or diseases. We have previously shown that biolistic delivery of an expression construct encoding inducible HSP70 (HSP70i) with one amino acid modification in the dendritic cell (DC) activating moiety 435–445 (HSP70iQ435A) to mouse skin resulted in significant immunosuppressive activity of autoimmune vitiligo, associated with fewer tissue infiltrating T cells. To prepare HSP70iQ435A as a potential therapeutic for autoimmune vitiligo, in this study we evaluated whether and how biolistic delivery of HSP70iQ435A in mice affects anti-tumor responses. We found that HSP70iQ435A in fact supports anti-tumor responses in melanoma-challenged C57BL/6 mice. Biolistic delivery of the HSP70iQ435A-encoding construct to mice elicited significant anti-HSP70 titers, and anti-HSP70 IgG and IgM antibodies recognize surface-expressed and cytoplasmic HSP70i in human and mouse melanoma cells. A peptide scan revealed that the anti-HSP70 antibodies recognize a specific C-terminal motif within the HSP70i protein. The antibodies elicited surface CD107A expression among mouse NK cells, representative of antibody-mediated cellular cytotoxicity (ADCC), supporting the concept, that HSP70iQ435A-encoding DNA elicits a humoral response to the stress protein expressed selectively on the surface of melanoma cells. Thus, besides limiting autoimmunity and inflammation, HSP70iQ435A elicits humoral responses that limit tumor growth and may be used in conjunction with immune checkpoint inhibitors to not only control tumor but to also limit adverse events following tumor immunotherapy.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12192-021-01229-x. 相似文献
957.
958.
Inmaculada Llamas Ana del Moral Victoria Béjar Mara Dolores Girón Rafael Salto Emilia Quesada 《FEMS microbiology letters》1997,156(2):251-257
The moderately halophilic bacterium Halomonas eurihalina strain F2-7, able to produce an exopolysaccharide, was found to contain two plasmids named pVE1 and pVE2, of 8.1 and 5.8 kb respectively. We found no evidence for the involvement of these plasmids in the expression of the mucoid phenotype. Restriction maps of both plasmids were constructed. Southern hybridization revealed similarities between them but excluded the existence of sequences homologous to other plasmids isolated from the Halomonas species. Neither pVE1 nor pVE2 displayed any homology with other plasmids isolated from moderate halophiles. The occurrence of similar plasmids in other strains of Halomonas eurihalina, isolated from hypersaline soils, has been detected. These small plasmids may be useful for the development of cloning vectors for moderately halophilic bacteria. 相似文献
959.
Francisco de Castro Sina M. Adl Stefano Allesina Richard D. Bardgett Thomas Bolger Johnathan J. Dalzell Mark Emmerson Thomas Fleming Diego Garlaschelli Jacopo Grilli Silja Emilia Hannula Franciska de Vries Zoë Lindo Aaron G. Maule Maarja
pik Matthias C. Rillig Stavros D. Veresoglou Diana H. Wall Tancredi Caruso 《Ecology and evolution》2021,11(22):16070
Ecologists have long debated the properties that confer stability to complex, species‐rich ecological networks. Species‐level soil food webs are large and structured networks of central importance to ecosystem functioning. Here, we conducted an analysis of the stability properties of an up‐to‐date set of theoretical soil food web models that account both for realistic levels of species richness and the most recent views on the topological structure (who is connected to whom) of these food webs. The stability of the network was best explained by two factors: strong correlations between interaction strengths and the blocked, nonrandom trophic structure of the web. These two factors could stabilize our model food webs even at the high levels of species richness that are typically found in soil, and that would make random systems very unstable. Also, the stability of our soil food webs is well‐approximated by the cascade model. This result suggests that stability could emerge from the hierarchical structure of the functional organization of the web. Our study shows that under the assumption of equilibrium and small perturbations, theoretical soil food webs possess a topological structure that allows them to be complex yet more locally stable than their random counterpart. In particular, results strongly support the general hypothesis that the stability of rich and complex soil food webs is mostly driven by correlations in interaction strength and the organization of the soil food web into functional groups. The implication is that in real‐world food web, any force disrupting the functional structure and distribution pattern of interaction strengths (i.e., energy fluxes) of the soil food webs will destabilize the dynamics of the system, leading to species extinction and major changes in the relative abundances of species. 相似文献
960.
Emilia Mellado Charles A. Specht Phillips W. Robbins David W. Holden 《FEMS microbiology letters》1996,143(1):69-76
Abstract A chitin synthase-like gene ( chsD ) was isolated from an Aspergillus fumigatus genomic DNA library. Comparisons with the predicted amino acid sequence from chsD reveals low but significant similarity to chitin synthases, to other N acetylglucosaminyltransferases (NodC from Rhizopus spp., HasA from Streptococcus spp. and DG42 from vertebrates. A chsD− mutant strain constructed by gene disruption has a 20% reduction in total mycelial chitin content; however, no differences between the wild-type strain and the chsD− strain were found with respect to morphology, chitin synthase activity or virulence in a neutropenic murine model of aspergillosis. The results show that the chsD product has an important but inessential role in the synthesis of chitin in A. fumigatus . 相似文献