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Marta Bassitta Joana M. Buades Ana Pérez-Cembranos Valentín Pérez-Mellado Barbara Terrasa Richard P. Brown Pilar Navarro Javier Lluch Jesús Ortega Jose A. Castro Antònia Picornell Cori Ramon 《Zoologica scripta》2020,49(6):668-683
The phylogenetic relationships among the wall lizards of the Podarcis hispanicus complex that inhabit the south-east (SE) of the Iberian Peninsula and other lineages of the complex remain unclear. In this study, four mitochondrial and two nuclear markers were used to study genetic relationships within this complex. The phylogenetic analyses based on mtDNA gene trees constructed with ML and BI, and a species tree using *BEAST support three divergent clades in this region: the Valencia, Galera and Albacete/Murcia lineages. These three lineages were also corroborated in species delimitation analyses based on mtDNA using bPTP, mPTP, GMYC, ABGD and BAPS. Bayesian inference species delimitation method (BPP) based on both nuclear data and a combined data set (mtDNA + nuclear) showed high posterior probabilities for these three SE lineages (≥0.94) and another Bayesian analysis (STACEY) based on combined data set recovered the same three groups in this region. Divergence time dating of the species tree provided an estimated divergence of the Galera lineage from the other SE group (Podarcis vaucheri, (Albacete/Murcia, Valencia)) at 12.48 Ma. During this period, the Betic–Rifian arc was isolated, which could have caused the isolation of the Galera form distributed to the south of the Betic Corridor. Although lizards from the Albacete/Murcia and Galera lineage are morphologically similar, they clearly represent distinct genetic lineages. The noteworthy separation of the Galera lineage enables us to conclude that this lineage must be considered as a new full species. 相似文献
3.
A conserved coronavirus epitope, critical in virus neutralization, mimicked by internal-image monoclonal anti-idiotypic antibodies. 下载免费PDF全文
Monoclonal antibody (MAb) 6A.C3 neutralizes transmissible gastroenteritis coronavirus (TGEV) and is specific for a conserved epitope within subsite Ac of the spike (S) glycoprotein of TGEV. Six hybridomas secreting anti-idiotypic (Ab2) MAbs specific for MAb 6A.C3 (Ab1) have been selected. All six MAbs inhibited the binding of Ab1 to TGEV and specifically cross-linked MAb1-6A.C3. Four of these hybridomas secreted gamma-type anti-idiotypic MAbs. The other two Ab2s (MAbs 9A.G3 and 9C.E11) were recognized by TGEV-specific antiserum induced in two species. This binding was inhibited by viruses of the TGEV group but not by serologically unrelated coronaviruses. These results indicate that MAb2-9A.G3 and MAb2-9C.E11 mimic an antigenic determinant present on the TGEV surface, and they were classified as beta-type ("internal-image") MAbs. TGEV-binding Ab3 antiserum was induced in 100% of mice immunized with the two beta-type MAb2s and in 25 to 50% of mice immunized with gamma-type MAb2. Both beta- and gamma-type Ab2s induced neutralizing Ab3 antibodies in mice that were mainly directed to antigenic subsite Ac of the S protein. 相似文献
4.
Conidia of the speciesFusarium culmorum /W.G.Sm./ Sacc. andFusarium graminearum Schwabe are characterized by variability in zearalenone production and dimensions depending on the substrate. The sporulation of isolates from some wheat eultivars have been deprived in vivo and in vitro in the first passage, but not their pathogenicity and toxic metabolites production. Nonsporulating strains produced lower quantités of zearalenone than sporulating ones. Liquid filtrates of such nonsporulating strains had a high phytotoxic effect on wheat caryopses. The crystalline toxin DAS /0,25 ug/ml/ had low phytotoxic effect on wheat caryopses. 相似文献
5.
H. Ant 《Plant Ecology》1969,18(1-6):374-386
Zusammenfassung Die Pflanzengesellschaften werden als objektive Einheiten der Erdoberfläche angesehen, die als Grundlage für biosoziologische Untersuchungen dienen können. Die verschiedenen bislang angewandten Untersuchungsverfahren zur quantitativen Erfassung des Tierartenbestandes eines einheitlichen Gebietes wereden angeführt und erörtert. Die eigenen Untersuchungen wurden in Probeflächen des Melico- und Carici-Fagetum durchgeführt. Dabei wurden mehrere Probequadrate von 25×25 cm abgesteckt und zu einer Probefläche zusammengefaßt. Zur Angabe der Frequenz und Abundanz wird ein Klassensystem benutzt (+, 1 bis 5). In Waldgesellschaften sind mindestens 8 Probequadrate erforderlich. Der Vergleich mehrerer einheitlicher Bestände ergibt die Konstanz (I bis V). Für das Carici-Fagetum lassen sich Abida secale, Clausilia parvula und Iphigena plicatula als Kenn-Arten ausscheiden. Die Artenzahl ist im Melico-Fagetum geringer. Einige Arten können evtl. als geographische Differentialarten angesehen werden.
Summary The plant associations are considered to be objective units of the earth surface which may be a basis for biosociological researches. The different methods used for quantitative studies of the animal species of a homogeneous area are recorded and discussed. Own studies of the Melico-Fagetum and Carici-Fagetum have been carried out in northwestern Germany. Several sample squares of 25×25 cm are marked out and treated as a whole called sample area. Frequency and abundancy are represented by five classes (1 to 5). In wood communities 8 sample squares are necessary. The constancy means the frequency within several homogeneous sites (I to V). Thus it was found that the Carici-Fagetum is characterized by Abida secale, Clausilia parvula and Iphigena plicatula as euconstant species. The number of species is less in the Melico-Fagetum. Some species may be defined as geographically differentiating species.相似文献
6.
Rui L. Mendes Helena L. Fernandes José A.P Coelho Joaquim M.S Cabral António M. F. Palavra Júlio M. Novais 《Journal of applied phycology》1994,6(3):289-293
Samples of the microalgaBotryococcus braunii were submitted to supercritical fluid extraction with carbon dioxide at 40 °C and pressures of 12.5, 20.0 and 30.0 MPa. The extraction yield and the fraction of the hydrocarbons in the extracts both increased with pressure and at 30 MPa these compounds were obtained rapidly. This behaviour is associated with the localization of the hydrocarbons outside the cell wall. In the extracts, which are fluid, golden and limpid, chlorophyll and phospholipids were not detected.Author for correspondence 相似文献
7.
Environmental influences on local amphibian diversity: the role of floods on river basins 总被引:2,自引:1,他引:1
We tested two hypotheses about boundary units and seven about environmental control of species diversity in order to explain geographical trends in the richness of amphibian species in the Mediterranean watershed of the southern coast of the Iberian Peninsula. The number of amphibian species tends to decrease from west to east. The longitudinal trend in the richness of amphibian species actually occurs on passing from one basin to another, but there is not any longitudinal trend within the basins. Multivariate analyses confirmed that the disturbances of episodic river-basin floodings were the principal factor which controls the richness of amphibian species. They explained 94.8% of the observed variations in the richness of amphibian species in this area, according to the intermediate disturbance hypothesis.We propose hydrographic basins as suitable geographical units for further biogeographical analysis and for considering the role of disturbances produced by floods in the environmental control of species diversity. 相似文献
8.
9.
Flavio Alexandre Carvalho Natália Valadares de Moraes Antônio Eduardo Miller Crotti Eduardo José Crevelin André Gonzaga dos Santos 《化学与生物多样性》2023,20(9):e202300492
Casearia species are found in the America, Africa, Asia, and Australia and present pharmacological activities, besides their traditional uses. Here, we reviewed the chemical composition, content, pharmacological activities, and toxicity of the essential oils (EOs) from Casearia species. The EO physical parameters and leaf botanical characteristics were also described. The bioactivities of the EOs from the leaves and their components include cytotoxicity, anti-inflammatory, antiulcer, antimicrobial, antidiabetic, antioxidant, antifungal, and antiviral activities. The main components associated with these activities are the α-zingiberene, (E)-caryophyllene, germacrene D, bicyclogermacrene, spathulenol, α-humulene, β-acoradiene, and δ-cadinene. Data on the toxicity of these EOs are scarce in the literature. Casearia sylvestris Sw. is the most studied species, presenting more significant pharmacological potential. The chemical variability of EOs components was also investigated for this species. Caseria EOs have relevant pharmacological potential and must be further investigated and exploited. 相似文献
10.
Ricardo O. Louro Teresa Catarino Carlos A. Salgueiro Jean LeGall António V. Xavier 《Journal of biological inorganic chemistry》1996,1(1):34-38
Using potentiometric titrations, two protons were found to participate in the redox-Bohr effect observed for cytochrome c
3 from Desulfovibrio vulgaris (Hildenborough). Within the framework of the thermodynamic model previously presented, this finding supports the occurrence
of a concerted proton-assisted 2e– step, ideally suited for the coupling role of cytochrome c
3 to hydrogenase. Furthermore, at physiological pH, it is shown that when sulfate-reducing bacteria use H2 as energy source, cytochrome c
3 can be used as a charge separation device, achieving energy transduction by energising protons which can be left in the acidic
periplasmic side and transferring deenergised electrons to sulfate respiration. This mechanism for energy transduction, using
a full thermodynamic data set, is compared to that put forward to explain the proton-pumping function of cytochrome c oxidase. 相似文献