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21.
Giancarlo Tesitore César Rodríguez-Bolaña Guillermo Goyenola Alejandra Kröger Martín Pacheco Maite Burwood Franco Teixeira de Mello 《Zeitschrift fur angewandte Ichthyologie》2020,36(6):849-851
This work provides new length-weight information for seven species of freshwater fishes. The analyzed specimens were collected monthly during a year (April 2018–March 2019) in a coastal lagoon system and its associated streams in southern Uruguay. During each sampling campaign, fishes were captured using gillnets in the lagoon and electrofishing in the streams. This study reports a new maximum size for four species and the first length-weight relationship report for Gymnogeophagus terrapurpura. Length-weight estimates and their confidence intervals are provided for all species. 相似文献
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Gehring Christoph Zelarayán Marcelo Correa Luz Ronildson Lima Almeida Rosângela Borges Boddey Robert Michael Leite Márcio Fernandes Alves 《Plant and Soil》2020,454(1-2):447-460
Plant and Soil - Aggressive ruderal plant species pose an increasing problem in anthropically degraded lands. They both affect and are affected by other vegetation and by soil fertility in their... 相似文献
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Tropical papaya (Carica papaya) and mountain papaya (Vasconcellea pubescens) fruits are characterised for their strong and particular aroma. The aroma of both fruits is different and dominated by esters, which are synthesised by alcohol acyltransferases (AATs). The ability to produce esters is contrasting, V. pubescens (VpAAT1) being a very active enzyme towards the production of benzyl acetate, whereas C. papaya (CpAAT1) is more active towards the production of ethyl butanoate and methyl butanoate, but not benzyl acetate. In order to understand the mechanism of action at the molecular level, the structural model of CpAAT1 protein was built by comparative modelling. Conformational interaction between the protein and several ligands was carried out by molecular docking. CpAAT1 structure showed two domains connected by a large crossover loop, with a solvent channel in the centre of the structure. CpAAT1 and VpAAT1 proteins showed similar 3D structures, including their catalytic sites, but their solvent channels showed differences in size and shape. CpAAT1 solvent channel is larger, in agreement with its higher selectivity for large acyl-CoA substrates. In addition, the most favourably predicted substrate orientation in CpAAT1 was observed for methanol and butanoyl-CoA, showing a perfect coincidence with the high production rate of methyl butanoate of C. papaya fruit. 相似文献
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Frank O. Aylward Bradon R. McDonald Sandra M. Adams Alejandra Valenzuela Rebeccah A. Schmidt Lynne A. Goodwin Tanja Woyke Cameron R. Currie Garret Suen Michael Poulsen 《Applied and environmental microbiology》2013,79(12):3724-3733
Sphingomonads comprise a physiologically versatile group within the Alphaproteobacteria that includes strains of interest for biotechnology, human health, and environmental nutrient cycling. In this study, we compared 26 sphingomonad genome sequences to gain insight into their ecology, metabolic versatility, and environmental adaptations. Our multilocus phylogenetic and average amino acid identity (AAI) analyses confirm that Sphingomonas, Sphingobium, Sphingopyxis, and Novosphingobium are well-resolved monophyletic groups with the exception of Sphingomonas sp. strain SKA58, which we propose belongs to the genus Sphingobium. Our pan-genomic analysis of sphingomonads reveals numerous species-specific open reading frames (ORFs) but few signatures of genus-specific cores. The organization and coding potential of the sphingomonad genomes appear to be highly variable, and plasmid-mediated gene transfer and chromosome-plasmid recombination, together with prophage- and transposon-mediated rearrangements, appear to play prominent roles in the genome evolution of this group. We find that many of the sphingomonad genomes encode numerous oxygenases and glycoside hydrolases, which are likely responsible for their ability to degrade various recalcitrant aromatic compounds and polysaccharides, respectively. Many of these enzymes are encoded on megaplasmids, suggesting that they may be readily transferred between species. We also identified enzymes putatively used for the catabolism of sulfonate and nitroaromatic compounds in many of the genomes, suggesting that plant-based compounds or chemical contaminants may be sources of nitrogen and sulfur. Many of these sphingomonads appear to be adapted to oligotrophic environments, but several contain genomic features indicative of host associations. Our work provides a basis for understanding the ecological strategies employed by sphingomonads and their role in environmental nutrient cycling. 相似文献
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Alejandro González Medina Lucas González Herrera M. Alejandra Perotti Gilberto Jiménez Ríos 《Experimental & applied acarology》2013,59(3):297-305
Despite the fact that mites were used at the dawn of forensic entomology to elucidate the postmortem interval, their use in current cases remains quite low for procedural reasons such as inadequate taxonomic knowledge. A special interest is focused on the phoretic stages of some mite species, because the phoront-host specificity allows us to deduce in many occasions the presence of the carrier (usually Diptera or Coleoptera) although it has not been seen in the sampling performed in situ or in the autopsy room. In this article, we describe two cases where Poecilochirus austroasiaticus Vitzthum (Acari: Parasitidae) was sampled in the autopsy room. In the first case, we could sample the host, Thanatophilus ruficornis (Küster) (Coleoptera: Silphidae), which was still carrying phoretic stages of the mite on the body. That attachment allowed, by observing starvation/feeding periods as a function of the digestive tract filling, the establishment of chronological cycles of phoretic behavior, showing maximum peaks of phoronts during arrival and departure from the corpse and the lowest values in the phase of host feeding. From the sarcosaprophagous fauna, we were able to determine in this case a minimum postmortem interval of 10 days. In the second case, we found no Silphidae at the place where the corpse was found or at the autopsy, but a postmortem interval of 13 days could be established by the high specificity of this interspecific relationship and the departure from the corpse of this family of Coleoptera. 相似文献
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Leyi Gong Xiaochun Han Tania Silva Yun-Chou Tan Bindu Goyal Parch Tivitmahaisoon Alejandra Trejo Wylie Palmer Heather Hogg Alam Jahagir Muzaffar Alam Paul Wagner Karin Stein Lubov Filonova Brad Loe Ferenc Makra David Rotstein Lubica Rapatova David Goldstein 《Bioorganic & medicinal chemistry letters》2013,23(12):3565-3569
A novel series of indole/indazole-aminopyrimidines was designed and synthesized with an aim to achieve optimal potency and selectivity for the c-Jun kinase family or JNKs. Structure guided design was used to optimize the series resulting in a significant potency improvement. The best compound (17) has IC50 of 3 nM for JNK1 and 20 nM for JNK2, with greater than 40-fold selectivity against other kinases with good physicochemical and pharmacokinetic properties. 相似文献