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51.
Rocha LC Luiz RF Rosset IG Raminelli C Seleghim MH Sette LD Porto AL 《Marine biotechnology (New York, N.Y.)》2012,14(4):396-401
Nine marine fungi (Aspergillus sclerotiorum CBMAI 849, Aspergillus sydowii Ce19, Beauveria felina CBMAI 738, Mucor racemosus CBMAI 847, Penicillium citrinum CBMAI 1186, Penicillium miczynskii Ce16, P. miczynskii Gc5, Penicillium oxalicum CBMAI 1185, and Trichoderma sp. Gc1) catalyzed the asymmetric bioconversion of iodoacetophenones 1-3 to corresponding iodophenylethanols 6-8. All the marine fungi produced exclusively (S)-ortho-iodophenylethanol 6 and (S)-meta-iodophenylethanol 7 in accordance to the Prelog rule. B. felina CBMAI 738, P. miczynskii Gc5, P. oxalicum CBMAI 1185, and Trichoderma sp. Gc1 produced (R)-para-iodophenylethanol 8 as product anti-Prelog. The bioconversion of para-iodoacetophenone 3 with whole cells of P. oxalicum CBMAI 1185 showed competitive reduction-oxidation reactions. 相似文献
52.
Debora Franceschini Paola Del Porto Silvia Piconese Emanuele Trella Daniele Accapezzato Marino Paroli Stefania Morrone Enza Piccolella Enea Spada Alfonso Mele John Sidney Alessandro Sette Vincenzo Barnaba 《PLoS pathogens》2012,8(6)
Caspase-dependent cleavage of antigens associated with apoptotic cells plays a prominent role in the generation of CD8+ T cell responses in various infectious diseases. We found that the emergence of a large population of autoreactive CD8+ T effector cells specific for apoptotic T cell-associated self-epitopes exceeds the antiviral responses in patients with acute hepatitis C virus infection. Importantly, they endow mixed polyfunctional type-1, type-2 and type-17 responses and correlate with the chronic progression of infection. This evolution is related to the selection of autoreactive CD8+ T cells with higher T cell receptor avidity, whereas those with lower avidity undergo prompt contraction in patients who clear infection. These findings demonstrate a previously undescribed strict link between the emergence of high frequencies of mixed autoreactive CD8+ T cells producing a broad array of cytokines (IFN-γ, IL-17, IL-4, IL-2…) and the progression toward chronic disease in a human model of acute infection. 相似文献
53.
Leandro H. Andrade lvaro T. Omori Andr L. M. Porto Joo V. Comasseto 《Journal of Molecular Catalysis .B, Enzymatic》2004,29(1-6):47-54
A series of novel organoseleno acetophenones (3a–f) have been synthesized. The microbial reduction of the seleno ketones (3) has been evaluated using whole cells of Rhizopus oryzae CCT 4964, Aspergillus terreus CCT 3320, A. terreus CCT 4083 and Emericella nidulans CCT 3119. These microorganisms showed Prelog and anti-Prelog stereoselectivity, leading to the arylselenoalcohols in moderate to high enantiomeric excesses. The organoselenium compounds were compatible with the biocatalytic conditions employed. 相似文献
54.
55.
Roseli Maria De Conti Andr L. M. Porto J. Augusto R. Rodrigues Paulo J. S. Moran Gilson P. Manfio Anita J. Marsaioli 《Journal of Molecular Catalysis .B, Enzymatic》2001,11(4-6):233-236
A Brazilian strain of the bacteria Serratia rubidaea CCT 5742 quantitatively reduced 4-tert-butylcyclohexanone and 4-methylcyclohexanone to the less thermodynamically stable diastereoisomeric alcohols cis-4-tert-butylcyclohexanol and cis-4-methylcyclohexanol with a diastereoisomeric excesses (de) of 96% and 44%, respectively. 2-Methylcyclohexanone was also totally reduced to the corresponding alcohols affording the trans-(+)-(1S, 2S)-2-methylcyclohexanol with 78% of de and an enantiomeric excess (ee) of 80%. The cis-(+)-(1S, 2R)-2-methylcyclohexanol was obtained in 98% ee. 相似文献
56.
We hypothesized that distribution and microhabitat use by imperilled chub Squalius torgalensis in the Torgal stream, Portugal, during low flows, were related to spatial patchiness in physical resources and shifts in ontogenetic preferences. We mapped fish abundance and sampled microhabitat use and availability via snorkelling. We used the coefficient of dispersion in abundance, and spatial autocorrelation analyses to characterize chub distribution, and Hurdle models to relate chub presence and abundance to habitat characteristics. We showed that chub displayed an aggregated distribution, apparently in association with patchily distributed and autocorrelated physical resources, such as debris, roots and aquatic vegetation. Microhabitat use generally was unrelated to velocity, and ontogenetic differences in microhabitat use were not substantial. Nevertheless, sometimes small chub preferred low-velocity patches with coarse substrata, debris and roots, whereas large chub preferred deeper patches with roots and aquatic vegetation. Results suggest that, in low flow conditions, chub respond to resource patchiness by congregating in favourable microhabitats, and that maintenance of mosaics of patches with variable substrata, cover and depth may be important for the persistence of fish in Mediterranean streams. 相似文献
57.
58.
Regional distribution patterns can predict the local habitat specialization of arachnids in heterogeneous landscapes of the Atlantic Forest
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Tiago Jordão Porto Ricardo Pinto‐da‐Rocha Pedro Luís Bernardo da Rocha 《Diversity & distributions》2018,24(3):375-386
Aim
This study formally evaluates the ability of three models to use geographical data on species distribution to predict the habitat use patterns of species in heterogeneous landscapes.Location
Species and habitats in the Brazilian Atlantic Rain Forest were investigated.Methods
Based on empirical data on harvestmen and scorpions, we estimated the strength of species association with preferred habitat and classified them as habitat generalists or habitat specialists. We compared these empirical results with predictions made using data on species range size (model 1), species occurrence in biomes (model 2) and species occurrence in habitats within the biomes (model 3).Results
We used 1,278 records of eight harvestman and two scorpion species that had specific determination and enough sampling numbers to allow safe identification of habitat specialization. We observed the following: (1) the extension of species occurrence did not influence the strength of species–habitat association (estimated by IndVal), which led us to reject model 1; (2) species habitat specialization derived from occurrences in biomes was 60% coincident with the classification derived from empirical data. This value is not different enough from the value expected by chance for these data, which also led us to reject model 2; and (3) species classification derived from secondary data about the habitats used had a significant coincidence of 80% with the empirical classification, which led us to accept model 3.Main conclusions
For correct classification of species habitat specialization using secondary distributional data, we recommend that future studies consider using the most accurate information available on the habitats used by species. Especially for megadiverse and understudied groups, information about habitats used is not easy to obtain, so it is important for researchers and institutions to register and disseminate this information, which could support many other studies.59.
Luís Reino Stefan Schindler Joana Santana Miguel Porto Rui Morgado Francisco Moreira Ricardo Pita António Mira John T. Rotenberry Pedro Beja 《European Journal of Wildlife Research》2018,64(4):48
Land use intensification may create habitats that organisms perceive as suitable, but where reproduction or survival is insufficient to maintain self-sustaining populations. Such conditions may qualify as ecological traps, but their existence is often hard to prove. Here, we provide a practical framework to evaluate a potential ecological trap resulting from mismatch between habitat preferences and predation risk, focusing on ground-nesting farmland birds of conservation concern. The framework is based on species-specific associations with safe or unsafe habitat types (i.e. field and landscape types with high or low nest survival), and the occurrence of risk avoidance (i.e. negative responses to predator abundances or to nest failure rates after controlling for habitat effects). Bird densities were far more influenced by field characteristics than landscape context. Corn bunting and fan-tailed warbler were associated with tall swards (safe habitats), and did not show risk avoidance. Tawny pipit and and Galerida larks were associated with short swards (unsafe habitats), with the former avoiding fields with high nest predation rates, and the later avoiding high mongoose abundances. Short-toed lark was associated with fields with short swards and low nest trampling rates. Results suggest that short-toed lark may be the most vulnerable to ecological trapping, because it nests on unsafe habitats and did not show predation risk avoidance. Our approach provides a practical first step to infer vulnerability to a potential ecological trap, though further research is needed to confirm this effect. Management actions increasing nest survival in short sward fields will likely favour grassland bird conservation in intensive Mediterranean farmland. 相似文献
60.
José Di Conza Juan A Ayala Ayelén Porto Marta Mollerach Gabriel Gutkind 《International microbiology》2005,8(4):287-290
The presence of class 1, 2, and 3 integrons was investigated in four pediatric isolates of Salmonella enterica ser. Typhimurium (S. Typhimurium). A class 1 integron was detected in one S. Typhimurium strain, the only one that also showed resistance to various aminoglycoside antibiotics. This integron, called InJR06, and the aminoglycoside resistance determinants were located in pS06, a large (> or = 55 kb) conjugative plasmid. A single mobile cassette (encoding the aminoglycoside adenylyltransferase ANT(3')-Ia) was detected in the variable region of InJR06, while the architecture of the attI1 and attC sites was conserved. 相似文献