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111.
112.
Ivania Cerón-Souza Benjamin L. Turner Klaus Winter Ernesto Medina Eldredge Bermingham Gonzalo N. Feliner 《Plant Ecology》2014,215(5):481-493
Factors modulating introgressive hybridization between the red mangrove species Rhizophora mangle and R. racemosa in spatially defined sites are poorly understood. To investigate this, we evaluated the reproductive phenology and the nutrient and physiological traits in those two species and their F1 hybrids genotyped with microsatellite data across a natural hybrid zone from the Pacific coast of Panama. We found no evidence that reproductive phenology represents a barrier to gene flow, because R. mangle and the F1 hybrids produced flowers and propagules throughout the annual cycle, while R. racemosa flowered only in the dry season. Soil nutrient concentrations decreased landward, while soil salinity varied only slightly. Foliar nutrients and δ15N signatures varied according to the soil nutrient gradient, but only foliar phosphorus and carbon varied among species. In contrast, two structural variables (height and trunk diameter) and leaf variables related to salinity tolerance (Na, Cl:Na, K:Na, cation:anion) and water-use efficiency (i.e., δ13C) differed among species, suggesting higher salinity tolerance for R. mangle and F1 hybrids compared with R. racemosa. We conclude that parental species and F1 hybrids differ in salinity tolerance and water-use efficiency, which could be associated with adaptive evolution of the red mangrove hybrid complex. 相似文献
113.
NMR assignment of intrinsically disordered proteins (IDPs) by conventional HN-detected methods is hampered by the small dispersion of the amide protons chemical shifts and exchange broadening of amide proton signals. Therefore several alternative assignment strategies have been proposed in the last years. Attempting to seize that dispersion of 13C′ and 15N chemical shifts holds even in IDPs, we recently proposed two 13C-detected experiments to directly correlate the chemical shifts of two consecutive 13C′–15N groups in proteins, i.e. without mediation of other nuclei. Main drawback of these experiments is the interruption of the connection at prolines. Here we present new 13C-detected experiments to correlate consecutive 13C′–15N groups in IDPs, hacacoNcaNCO and hacaCOncaNCO, that overcome this limitation. Moreover, the experiments provide recognition of glycine residues, thereby facilitating the assignment process. 相似文献
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115.
Einar Vargas-Bello-Pérez Gonzalo Íñiguez-González Nathaly Cancino-Padilla Juan J. Loor Philip C. Garnsworthy 《Archives of animal nutrition》2016,70(4):322-332
The aim of this study was to elucidate the effect of dietary supplementation of soybean oil (SO) and hydrogenated palm oil (HPO) on the transport of fatty acids (FA) within plasma lipoproteins in lactating and non-lactating cows. Three lactating and three non-lactating Holstein cows were used in two different 3 × 3 Latin square experiments that included three periods of 21 d. Dietary treatments for lactating cows consisted of a basal diet (control; no fat supplement) and fat-supplemented diets containing SO (500 g/d per cow) or HPO (500 g/d per cow). For non-lactating cows, dietary treatments consisted of a basal diet (control; no fat supplement) and fat-supplemented diets containing SO (170 g/d per cow) or HPO (170 g/d per cow). Compared with the control and SO diet, HPO addition increased (p < 0.05) the concentration of C16:0, C18:0, C18:2cis-9,12, C18:3cis-9,12,15 and total saturated and polyunsaturated FA in the plasma of lactating cows. In non-lactating cows, the SO addition increased the plasma concentration of C18:1trans-11. In lactating cows, concentrations of C16:0, C18:0 and total saturated FA were increased (p < 0.05) by HPO addition in the high-density lipoprotein (HDL). Total saturated FA were increased (p < 0.05) by HPO in very-low-density lipoprotein (VLDL). In non-lactating cows, the concentration of C18:0 was increased (p < 0.05) by HPO in HDL, whereas C18:1trans-11 was increased (p < 0.05) by SO in the low-density lipoprotein. Overall, it was found that distribution and transport of FA within the bovine plasma lipoproteins may be influenced by chain length and degree of unsaturation of dietary lipids. Also, the distribution of individual FA isomers such as C18:1trans-11 and C18:2cis-9,trans-11 may vary depending on the physiological state of the cow (lactating or non-lactating), and are increased in plasma (lactating cows) and the HDL (non-lactating cows) when cows are fed SO. 相似文献
116.
Eco‐morphological differentiation in Lake Magadi tilapia,an extremophile cichlid fish living in hot,alkaline and hypersaline lakes in East Africa 下载免费PDF全文
Geraldine D. Kavembe Andreas F. Kautt Gonzalo Machado‐Schiaffino Axel Meyer 《Molecular ecology》2016,25(7):1610-1625
Ecological diversification through divergent selection is thought to be a major force during the process of adaptive radiations. However, the large sizes and complexity of most radiations such as those of the cichlids in the African Great Lakes make it impossible to infer the exact evolutionary history of any population divergence event. The genus Alcolapia, a small cichlid lineage endemic to Lakes Magadi and Natron in East Africa, exhibits phenotypes similar to some of those found in cichlids of the radiations of the African Great Lakes. The simplicity within Alcolapia makes it an excellent model system to investigate ecological diversification and speciation. We used an integrated approach including population genomics based on RAD‐seq data, geometric morphometrics and stable isotope analyses to investigate the eco‐morphological diversification of tilapia in Lake Magadi and its satellite lake Little Magadi. Additionally, we reconstructed the demographic history of the species using coalescent simulations based on the joint site frequency spectrum. The population in Little Magadi has a characteristically upturned mouth—possibly an adaptation to feeding on prey from the water surface. Eco‐morphological differences between populations within Lake Magadi are more subtle, but are consistent with known ecological differences between its lagoons such as high concentrations of nitrogen attributable to extensive guano deposits in Rest of Magadi relative to Fish Springs Lagoon. All populations diverged simultaneously only about 1100 generations ago. Differences in levels of gene flow between populations and the effective population sizes have likely resulted in the inferred heterogeneous patterns of genome‐wide differentiation. 相似文献
117.
Antonella Santoro Anna Rita CappelloMarianna Madeo Emanuela MartelloDomenico Iacopetta Vincenza Dolce 《Biochimica et Biophysica Acta (BBA)/General Subjects》2011
Background
Fosfomycin is widely used to treat urinary tract and pediatric gastrointestinal infections of bacteria. It is supposed that this antibiotic enters cells via two transport systems, including the bacterial Glycerol-3-phosphate Transporter (GlpT). Impaired function of GlpT is one mechanism for fosfomycin resistance.Methods
The interaction of fosfomycin with the recombinant and purified GlpT of Escherichia coli reconstituted in liposomes has been studied. IC50 and the half-saturation constant of the transporter for external fosfomycin (Ki) were determined by transport assay of [14C]glycerol-3-phosphate catalyzed by recombinant GlpT. Efficacy of fosfomycin on growth rates of GlpT defective bacteria strains transformed with recombinant GlpT was measured.Results
Fosfomycin, externally added to the proteoliposomes, poorly inhibited the glycerol-3-phosphate/glycerol-3-phosphate antiport catalyzed by the reconstituted transporter with an IC50 of 6.4 mM. A kinetic analysis revealed that the inhibition was completely competitive, that is, fosfomycin interacted with the substrate-binding site and the Ki measured was 1.65 mM. Transport assays performed with proteoliposomes containing internal fosfomycin indicate that it was not very well transported by GlpT. Complementation study, performed with GlpT defective bacteria strains, indicated that the fosfomycin resistance, beside deficiency in antibiotic transporter, could be due to other gene defects.Conclusions
The poor transport observed in a reconstituted system together with the high value of Ki and the results of complementation study well explain the usual high dosage of this drug for the treatment of the urinary tract infections.General significance
This is the first report regarding functional analysis of interaction between fosfomycin and GlpT. 相似文献118.
Maria Kahn Walter H. J. Ward Nicole LaRue Michael Kalnoky Sampa Pal Gonzalo J. Domingo 《The journal of histochemistry and cytochemistry》2015,63(6):454-458
Cytochemical staining remains an efficient way of identifying females who are heterozygous for the X chromosome-linked glucose-6-phosphate dehydrogenase (G6PD) gene. G6PD is highly polymorphic with certain alleles resulting in low intracellular G6PD activity in red blood cells. Low intracellular G6PD activity is associated with a risk of severe hemolysis when exposed to an oxidative stress such as fava beans, certain drugs and infections. Heterozygous females express the enzyme from both X-chromosome alleles resulting in two red blood cell populations each with G6PD enzyme characteristics representative of each allele; for example, normal and deficient. Cytochemical staining is the only way to determine the relative representation of each allele in red blood cells, a feature that is critical when assessing the risk for severe hemolysis when exposed to an oxidant such as the anti-malarial drug primaquine. This letter discusses red blood cell integrity with respect to the cytofluorometric assays for G6PD activity. An approach to making this test more robust is suggested. The approach makes this test more reliable and extends its use to a broader range of blood specimens. 相似文献
119.
Daniel Cortés-Borda Gonzalo Guillén-Gosálbez Laureano Jiménez Esteller 《The International Journal of Life Cycle Assessment》2013,18(5):948-957