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51.
Despite the growing number of genomes published or currently being sequenced, there is a relative paucity of software for functional classification of newly discovered genes and their assignment to metabolic pathways. Available software for such analyses has a very steep learning curve and requires the installation, configuration, and maintenance of large amounts of complex infrastructure, including complementary software and databases. Many such tools are restricted to one or a few data sources and classification schemes. In this work, we report an automated system for gene annotation and metabolic pathway reconstruction (ASGARD), which was designed to be powerful and generalizable, yet simple for the biologist to install and run on centralized, commonly available computers. It avoids the requirement for complex resources such as relational databases and web servers, as well as the need for administrator access to the operating system. Our methodology contributes to a more rapid investigation of the potential biochemical capabilities of genes and genomes by the biological researcher, and is useful in biochemical as well as comparative and evolutionary studies of pathways and networks. 相似文献
52.
Melo MS Guimarães AG Santana MF Siqueira RS De Lima Ado C Dias AS Santos MR Onofre AS Quintans JS De Sousa DP Almeida JR Estevam CS Araujo BS Quintans-Júnior LJ 《Biological research》2011,44(4):363-368
The anti-inflammatory and redox protective effects of the citronellal (CT) were evaluated using in vivo and in vitro tests. Intraperitoneal (i.p.) administration of CT (50, 100, and 200 mg/kg) inhibited (p < 0.05) the carrageenan-induced leukocyte migration to the peritoneal cavity. Additionally, the carrageenan- and arachidonic acid-induced rat hind paw edema was significantly inhibited (p < 0.05) by i.p. administration of 100 and 200 mg/kg of the compound. When the redox activity was evaluated, CT (200 mg/kg) significantly reduced hepatic lipoperoxidation (p < 0.001), as well as oxidation of plasmatic (p < 0.05) and hepatic (p < 0.01) proteins. The results of the present study support the hypothesis that CT possesses anti-inflammatory and redox protective activities. It is suggested that its effects are associated with the inhibition of the enzymes in the arachidonic acid pathway, which prevent cell migration by inhibiting leukotriene production, edema formation and the increase of reactive oxygen species in tissues. Therefore, CT is of potential benefit to manage inflammatory disorders and correlated damages caused by oxidant agents. 相似文献
53.
Luis?Sánchez-PulidoEmail author Ana?M?Rojas Karel?H?van Wely Carlos?Martinez-A Alfonso?Valencia 《BMC bioinformatics》2004,5(1):91
Background
The Split ends (Spen) family are large proteins characterised by N-terminal RNA recognition motifs (RRMs) and a conserved SPOC (Spen paralog and ortholog C-terminal) domain. The aim of this study is to characterize the family at the sequence level. 相似文献54.
João H. D. Lima Nicholas J. Minter Renata G. Netto 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2017,50(4):576-590
Apportioning trace fossils to producers is significant for palaeoecological and palaeoenvironmental studies. A tracemaker is usually attributed through the comparison of the morphology of the trace to the body plans of modern and extinct animals. However, hypotheses of tracemaker identifications may be tested with the use of further methods. This contribution aims to evaluate the potential tracemakers of a trackway‐dominated ichnofauna preserved in the siltstone–claystone rhythmites of the Pennsylvanian Rio do Sul Formation in the southern Brazil. These deposits are typical of the deglaciation phase of the Late Palaeozoic Ice Age of Gondwana in the Paraná Basin. Thus, the parameters applied in this work are as follows: (1) functional analyses of the traces to infer the biomechanics of the locomotion of the producer; and (2) neoichnology, whereby modern traces whose producers are known are compared to those of the ichnofauna in question. The conclusions obtained with these methods strongly support millipedes as the producers of Diplichnites gouldi and Diplopodichnus biformis. The malacostracan crustacean‐related ichnogenera are Umfolozia sinuosa and Gluckstadtella elongata, produced by syncarids or peracarids, while isopods are suggested as the tracemakers of Glaciichnium isp. and Protovirgularia dichotoma. In terms of branchiopod crustaceans, Cruziana problematica is attributed to notostracans. Helminthoidichnites tenuis, Mermia carickensis and Treptichnus pollardi are considered traces produced by insect larvae. The palaeobiology of the tracemakers that produced the ichnofauna preserved in the rhythmites of the Rio do Sul Formation permits inferences that terrestrial (millipedes) and aquatic (crustaceans and insect larvae) animals colonized the sediments. This conclusion points to a dynamic depositional environment, with changing physical and chemical parameters conditioning the biota. 相似文献
55.
T. Corrêa de Souza P. César Magalhães F. José Pereira E. Mauro de Castro S. Netto Parentoni 《Acta Physiologiae Plantarum》2011,33(5):1877-1885
This study was carried out to evaluate maize plants of different recurrent selection cycles of the variety (Zea mays L.—Saracura-BRS-4154) regarded to genetic gains, morphophysiology, and grain yield, achieved over the selection cycles under
intermittent flooding of the soil. This variety has the capacity to survive and produce in temporarily flooded soils and was
developed by the National Maize and Sorghum Research Center (EMBRAPA). The experiment was conducted in greenhouse by using
ten alternating selection cycles (Cycle 1–18) and BR 107 a variety known for its susceptibility to flooding. The flooding
initiated at six-leaf stage by applying 50 mm of water three times a week. At flowering, the following parameters were evaluated:
rate of leaf photosynthesis, stomatal conductance, intercellular CO2 concentration, transpiration rate, photosynthetically active leaf area, root porosity, relative chlorophyll content, grain
yield, harvest index, ear length, and interval between male and female flowering. Yield as a function of root porosity and
photosynthesis were also evaluated. An index was created in this study, in order to help the discussion of the characteristics
evaluated, it was called “Relative Tolerance Value—RTV”, only gaseous exchange measurements was not included in this index.
By the way, it was observed throughout the selection cycles an increase in all gaseous exchange parameters, being the cycle
18, the one which presented the greatest averages. RTV for leaf area showed the greatest values for cycles 7 and 18, whereas
root porosity, chlorophyll relative content, and harvest index, the greater RTV values were found in cycles 17 and 18. The
largest grain yield RTV was observed in cycle 7, followed by cycles 13, 15, and 18. Flooding resulted in longer Anthesis-Silking
Interval, especially for the first cycles. At flooding condition, grain yield was strongly related to root porosity (R
2 = 0.66). These results showed that the selection cycles of “Saracura” maize improved some morphophysiologic characters, which
favor their survival in flooded environments, also resulting in higher productivity. 相似文献
56.
Leão-Helder AN Krikken AM Gellissen G van der Klei IJ Veenhuis M Kiel JA 《FEBS letters》2004,577(3):491-495
ATG genes are required for autophagy-related processes that transport proteins/organelles destined for proteolytic degradation to the vacuole. Here, we describe the identification and characterisation of the Hansenula polymorpha ATG21 gene. Its gene product Hp-Atg21p, fused to eGFP, had a dual location in the cytosol and in peri-vacuolar dots. We demonstrate that Hp-Atg21p is essential for two separate modes of peroxisome degradation, namely glucose-induced macropexophagy and nitrogen limitation-induced microautophagy. In atg21 cells subjected to macropexophagy conditions, sequestration of peroxisomes tagged for degradation is initiated but fails to complete. 相似文献
57.
Duangrudee Cherdwongcharoensuk Maria João Oliveira Artur Perez Águas 《Biological trace element research》2010,136(2):197-203
The in vivo dynamics of selenium (Se) and mercury (Hg) interaction was studied in mouse tissues using direct visualization
of individual Se, Hg, and SeHg particles on the surface of circulating erythrocytes. This high-resolution detection of Se
and Hg was obtained by scanning electron microscopy coupled to X-ray microanalysis. BALB/c mice were injected in the peritoneal
cavity with Se and Hg salts, and the animals were sacrificed 3 min after the Hg injection. Only a minority (9%) of the metal
dots seen on mouse liver erythrocytes were SeHg complexes when Se and Hg salts were mixed together before injection. In contrast,
the majority (73%) of metal dots on liver erythrocytes were SeHg complexes if Se was injected at least 5 min before Hg injection.
All metal dots on liver erythrocytes were of SeHg complexes if Se was injected 9 or 12 min before the Hg injection. We conclude
that the formation of stable in vivo SeHg complexes requires preliminary interaction of Se with a putative serum factor before
complexes between Se and Hg are formed and are bound to the erythrocyte cell surface. 相似文献
58.
Alves Leticia Rodrigues Rossatto Davi Rodrigo Rossi Mônica Lanzoni Martinelli Adriana Pinheiro Gratão Priscila Lupino 《Protoplasma》2020,257(2):597-605
Protoplasma - The application of Se to plants growing under Cd contamination may become an alternative strategy to minimize Cd damage. However, there is no specific information available regarding... 相似文献
59.
Dos Santos RA Batista J Rosa SI Torquato HF Bassi CL Ribeiro TA De Sousa PT Bessera AM Fontes CJ Da Silva LE Piuvezam MR 《Parasitology》2011,138(10):1224-1233
Leishmaniasis is one of the neglected diseases. High cost, systemic toxicity, and diminished efficacy due to development of resistance by the parasites has a negative impact on the current treatment options. Thus, the search for a new, effective and safer anti-leishmanial drug becomes of paramount importance. Compounds derived from natural products may be a better and cheaper source in this regard. This study evaluated the in vitro anti-leishmanial activity of Spiranthera odoratíssima (Rutaceae) fractions and isolated compounds, using promastigote and amastigote forms of different Leishmania species. J774 A.1 macrophage was used as the parasite host cell for the in vitro assays. Evaluations of cytoxicity, nitric oxide (NO), interleukin-10 and in silico analysis were carried out. In vitro experiments showed that the fruit hexanic fraction (Fhf) and its alkaloid skimmianine (Skm) have a significant (P<0·001) effect against L. braziliensis. This anti-L. braziliensis activity of Fhf and Skm was due to increased production of NO and attenuation of IL-10 production in the macrophages at concentrations ranging from 1·6 to 40·0 μg/ml. The in silico assay demonstrated significant interaction between Skm and amino acid residues of NOS2. Skm is thus a promising drug candidate for L. braziliensis due to its potent immunomodulatory activity. 相似文献
60.
Marques MP Girão T Pedroso De Lima MC Gameiro A Pereira E Garcia P 《Biochimica et biophysica acta》2002,1589(1):63-70
Cytotoxicity and cell growth inhibition studies were performed for three distinct polynuclear platinum(II) complexes of spermidine, which showed to have significant cytotoxic and antiproliferative properties on the HeLa cancer cell line. The chemical environment of the metal centres in the drugs, as well as the coordination pattern of the ligand, were found to be strongly determinant of their cytotoxic ability. In the light of the results gathered, the most effective anticancer compound among the ones tested (IC50=5 microM) was found to be the one displaying three difunctional (PtCl2N2) moieties ((PtCl2)3(spd)2). Both the cytotoxic activity and the antiproliferative properties of the complexes studied showed to be irreversible for all the concentrations tested. 相似文献