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1.
Molecular and immunological characterization of the major outer membrane proteins of Brucella 总被引:2,自引:0,他引:2
Axel Cloeckaert Jean-Michel Verger Maggy Grayon Nieves Vizcaíno 《FEMS microbiology letters》1996,145(1):1-8
Abstract Saccharomyces cerevisiae exponentially growing in basic or 0.7 M NaCl medium were isotopically labelled with 35 S-methionine, followed by protein separation and quantification by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) combined with computerised image analysis. The electrophoretic separation resolved about 650 proteins of which 13 displayed significant and at least 2-fold changes in rate of synthesis during saline growth. By sequencing of 2D-PAGE resolved proteins, one of the 8 induced spot, p42.9/5.5, was shown to correspond to the full length (containing the N-terminal extension) product of the GPD 1 gene encoding the cytoplasmic glycerol 3-phosphate dehydrogenase. The expression of the TDH 3 gene, glyceraldehyde 3-phosphate dehydrogenase, and the ENO 2 gene, enolase, decreased during growth in NaCl medium, declines hypothesised to have an impact on the flux to glycerol. 相似文献
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Legionella pneumophila in Cooling Towers: Fluctuations in Counts, Determination of Genetic Variability by Pulsed-Field Gel Electrophoresis (PFGE), and Persistence of PFGE Patterns 下载免费PDF全文
Sonia Ragull Marian Garcia-Nuez Maria Luisa Pedro-Botet Nieves Sopena Maria Esteve Rafael Montenegro Miquel Sabri 《Applied microbiology》2007,73(16):5382-5384
The concentrations of Legionella pneumophila in cooling towers may vary considerably over short periods of time, producing significant fluctuations throughout the year. Despite genetic variability, in small geographical areas the same indistinguishable pulsed-field gel electrophoresis patterns may be shared among different cooling towers and persist over time. 相似文献
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Juan A. Pajares Gonzalo Álvarez David R. Hall Paul Douglas Felix Centeno Nieves Ibarra Martin Schroeder Stephen A. Teale Zhiying Wang Shanchun Yan Jocelyn G. Millar Lawrence M. Hanks 《Entomologia Experimentalis et Applicata》2013,149(2):118-127
The small white‐marmorated longicorn beetle, Monochamus sutor (L.) (Coleoptera: Cerambycidae), is widely distributed throughout Europe and Asia. It is a potential vector of the pine wood nematode, Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle, the causal agent of the devastating pine wilt disease. Volatiles were collected from both male and female beetles after maturation feeding. In analyses of these collections using gas chromatography (GC) coupled to mass spectrometry, a single male‐specific compound was detected and identified as 2‐(undecyloxy)‐ethanol. In analyses by GC coupled to electroantennography the only consistent responses from both female and male antennae were to this compound. Trapping tests were carried out in Spain, Sweden, and China. 2‐(Undecyloxy)‐ethanol was attractive to both male and female M. sutor beetles. A blend of the bark beetle pheromones ipsenol, ipsdienol, and 2‐methyl‐3‐buten‐2‐ol was also attractive to both sexes in Spain and Sweden, and further increased the attractiveness of the 2‐(undecyloxy)‐ethanol. The host plant volatiles α‐pinene, 3‐carene, and ethanol were weakly attractive, if at all, in all three countries and did not significantly increase the attractiveness of the blend of 2‐(undecyloxy)‐ethanol and bark beetle pheromones. 2‐(Undecyloxy)‐ethanol is thus proposed to be the major, if not only, component of the male‐produced aggregation pheromone of M. sutor, and its role is discussed. This compound has been reported as a pheromone of several other Monochamus species and is another example of the parsimony that seems to exist among the pheromones of many of the Cerambycidae. Traps baited with 2‐(undecyloxy)‐ethanol and bark beetle pheromones should be useful for monitoring and control of pine wilt disease, should M. sutor be proven to be a vector of the nematode. 相似文献
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María-Eugenia Guazzaroni Florian-Alexander Herbst Iván Lores Javier Tamames Ana Isabel Peláez Nieves López-Cortés María Alcaide Mercedes V Del Pozo José María Vieites Martin von Bergen José Luis R Gallego Rafael Bargiela Arantxa López-López Dietmar H Pieper Ramón Rosselló-Móra Jesús Sánchez Jana Seifert Manuel Ferrer 《The ISME journal》2013,7(1):122-136
Microbial metabolism in aromatic-contaminated environments has important ecological implications, and obtaining a complete understanding of this process remains a relevant goal. To understand the roles of biodiversity and aromatic-mediated genetic and metabolic rearrangements, we conducted ‘OMIC'' investigations in an anthropogenically influenced and polyaromatic hydrocarbon (PAH)-contaminated soil with (Nbs) or without (N) bio-stimulation with calcium ammonia nitrate, NH4NO3 and KH2PO4 and the commercial surfactant Iveysol, plus two naphthalene-enriched communities derived from both soils (CN2 and CN1, respectively). Using a metagenomic approach, a total of 52, 53, 14 and 12 distinct species (according to operational phylogenetic units (OPU) in our work equivalent to taxonomic species) were identified in the N, Nbs, CN1 and CN2 communities, respectively. Approximately 10 out of 95 distinct species and 238 out of 3293 clusters of orthologous groups (COGs) protein families identified were clearly stimulated under the assayed conditions, whereas only two species and 1465 COGs conformed to the common set in all of the mesocosms. Results indicated distinct biodegradation capabilities for the utilisation of potential growth-supporting aromatics, which results in bio-stimulated communities being extremely fit to naphthalene utilisation and non-stimulated communities exhibiting a greater metabolic window than previously predicted. On the basis of comparing protein expression profiles and metagenome data sets, inter-alia interactions among members were hypothesised. The utilisation of curated databases is discussed and used for first time to reconstruct ‘presumptive'' degradation networks for complex microbial communities. 相似文献
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Manuel Nieves‐Cordones Alberto Lara Reyes Rdenas Jesús Amo Rosa María Rivero Vicente Martínez Francisco Rubio 《Plant, cell & environment》2019,42(8):2357-2371
Root cells take up K+ from the soil solution, and a fraction of the absorbed K+ is translocated to the shoot after being loaded into xylem vessels. K+ uptake and translocation are spatially separated processes. K+ uptake occurs in the cortex and epidermis whereas K+ translocation starts at the stele. Both uptake and translocation processes are expected to be linked, but the connection between them is not well characterized. Here, we studied K+ uptake and translocation using Rb+ as a tracer in wild‐type Arabidopsis thaliana and in T‐DNA insertion mutants in the K+ uptake or translocation systems. The relative amount of translocated Rb+ to the shoot was positively correlated with net Rb+ uptake rates, and the akt1 athak5 T‐DNA mutant plants were more efficient in their allocation of Rb+ to shoots. Moreover, a mutation of SKOR and a reduced plant transpiration prevented the full upregulation of AtHAK5 gene expression and Rb+ uptake in K+‐starved plants. Lastly, Rb+ was found to be retrieved from root xylem vessels, with AKT1 playing a significant role in K+‐sufficient plants. Overall, our results suggest that K+ uptake and translocation are tightly coordinated via signals that regulate the expression of K+ transport systems. 相似文献
9.
Lavado Nieves de la Concepción Juan García Babiano Reyes Cintas Pedro Light Mark E. 《Origins of life and evolution of the biosphere》2019,49(3):163-185
Origins of Life and Evolution of Biospheres - In line with the postulated intermediacy of aminoxazoles derived from small sugars toward the direct assembly of nucleoside precursors, we show here a... 相似文献
10.
Itziar Lanas Piedad Gallego Luisa Martin Javier Fernandez Angel Alonso Juana Elena-Rosello Antonio Blazquez Nieves Villalobos Hilario Guerra 《Plant Growth Regulation》2006,49(1):49-60
High production of viable somatic embryos was obtained from cultured anthers in the second phase of meiosis, using microscopic
level observations of tetrads. The medium with the greatest embryogenic efficiency was H6, composed of Murashige and Skoog
(MS) medium with 2 mg l−1 of 2,4-dichlorophenoxyacetic acid (2,4-D) and 0.5 mg l−1 of kinetin. All (100%) of the somatic embryos obtained germinated and produced 63% green and 37% albino seedlings. In general,
embryogenic calli had a higher ion concentration than non-embryogenic calli, with the exception of calcium whose concentration
was higher in non-embryogenic calli. The calli induced in the different media differed in their sucrose and starch compositions.
The most embryogenic medium H6-induced calli with the highest sucrose concentration and the lowest starch concentration, before
visible embryos were observed. In the leaves of the albino seedlings, sucrose concentrations were very high while those of
starch were very low. Ion concentrations were also lower in albino plants than in the leaves of green seedlings, with the
exception of calcium, whose concentration was higher. Most of the albino individuals were homozygous, even when their progenitors
were heterozygous, thereby confirming their haploid nature. 相似文献