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951.
Gabriela C. Canton Amanda A. Bertolazi Antônio J. D. Cogo Frederico Jacob Eutrópio Juliana Melo Sávio Bastos de Souza Cesar A. Krohling Eliemar Campostrini Ary Gomes da Silva Arnoldo R. Façanha Nuno Sepúlveda Cristina Cruz Alessandro C. Ramos 《Mycorrhiza》2016,26(5):475-487
At relatively low concentrations, the element manganese (Mn) is essential for plant metabolism, especially for photosynthesis and as an enzyme antioxidant cofactor. However, industrial and agricultural activities have greatly increased Mn concentrations, and thereby contamination, in soils. We tested whether and how growth of Pisolithus tinctorius is influenced by Mn and glucose and compare the activities of oxidative stress enzymes as biochemical markers of Mn stress. We also compared nutrient accumulation, ecophysiology, and biochemical responses in Eucalyptus grandis which had been colonized by the ectomycorrhizal Pisolithus tinctorius with those which had not, when both were exposed to increasing Mn concentrations. In vitro experiments comprised six concentrations of Mn in three concentrations of glucose. In vivo experiments used plants colonized by Pisolithus tinctorius, or not colonized, grown with three concentrations of Mn (0, 200, and 1000 μM). We found that fungal growth and glucose concentration were correlated, but these were not influenced by Mn levels in the medium. The anti-oxidative enzymes catalase and glutathione S-transferase were both activated when the fungus was exposed to Mn. Also, mycorrhizal plants grew more and faster than non-mycorrhizal plants, whatever Mn exposure. Photosynthesis rate, intrinsic water use efficiency, and carboxylation efficiency were all inversely correlated with Mn concentration. Thus, we originally show that the ectomycorrhizal fungus provides protection for its host plants against varying and potentially toxic concentrations of Mn. 相似文献
952.
Purification and molecular characterization of a novel mannose‐specific lectin from Dioclea reflexa hook seeds with inflammatory activity
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Vanir R. Pinto‐Junior Jorge L. A. Correia Ronniery I. Pereira Francisco N. Pereira‐Junior Mayara Q. Santiago Vinicius J. S. Osterne Juliana C. Madeira João B. Cajazeiras Celso S. Nagano Plinio Delatorre Ana M. S. Assreuy Kyria S. Nascimento Benildo S. Cavada 《Journal of molecular recognition : JMR》2016,29(4):134-141
A novel lectin present in Dioclea reflexa seeds (DrfL) was discovered and described in this study. DrfL was purified in a single step by affinity chromatography in a Sephadex G‐50 column. The lectin strongly agglutinated rabbit erythrocytes and was inhibited by α‐methyl‐d ‐mannoside, d ‐mannose, and d ‐glucose. The hemagglutinating activity of DrfL is optimum at pH 5.0–7.0, stable up to 50 °C, and dependent on divalent cations. Similar to other lectins of the subtribe Diocleinae, the analysis by mass spectrometry indicated that DrfL has three chains (α, β, and γ) with masses of 25 562, 12 874, and 12 706 Da, respectively, with no disulfide bonds or glycosylation. DrfL showed inflammatory activity in the paw edema model and exhibited low cytotoxicity against Artemia sp. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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955.
André dos Santos Bragança Gil Climbiê Ferreira Hall Volker Bittrich Maria do Carmo Estanislau do Amaral 《Nordic Journal of Botany》2016,34(5):559-564
A new species of Neomarica from the Brazilian Atlantic Forest is described and illustrated. Neomarica sergipensis A. Gil & M.C.E. Amaral sp. nov. (Trimezieae, Iridoideae, Iridaceae) grows in restinga forests (forests on the coastal plains dominated by sandy soils) in the state of Sergipe, northeastern Brazil. The new species resembles Neomarica northiana, especially due to the white flowers with the basal third of the tepals yellow and covered by brown maculae, but differs by the inner tepals of with the center of the apical third is tinted violet to purple, yellow stigmatic crests with fimbriate to erose margins, and the endemic occurrence in Sergipe. 相似文献
956.
Maria Cristina Silva Juliana Arriel Torres Alexandre A. Castro Elaine F.F. da Cunha Luiz Carlos Alves de Oliveira Angelita Duarte Corrêa 《Journal of biomolecular structure & dynamics》2016,34(9):1839-1848
Water pollution is a significant and growing problem throughout the world, especially in developing countries. In order to minimize environmental problems, catalysts have increasingly been designed to remove pollutants from the water. In an attempt to innovate by the creation of new low-cost alternatives to efficiently remove pollutants, the enzymatic treatment has been intensely studied for this purpose. Reactions catalyzed by enzymes are able to perform specific treatments, commonly with high rates of the final products. With this, the enzyme, peroxidase, is a promising candidate as a bioremediation catalyst. The efficiency of oxidoreductive enzymes, such as horseradish peroxidase (HRP) and soybean peroxidase (SP) have been studied, given that their performance depends on the substrate. In this investigation, experimental techniques and theoretical calculations have been employed in order to investigate the oxidative process for the ferulic acid and bromophenol blue dyes, performed by HRP and SP. Both enzymes showed a comparable behavior with respect to ferulic acid substrate. On the other hand, by utilizing bromophenol blue dye as a substrate, the behavior of the employed catalysts was significantly different. Experimental data have shown that HRP was more active toward bromophenol blue when compared to ferulic acid, being more rapidly degraded by the HRP enzyme. This tendency was confirmed by our theoretical docking, PM6 semi-empirical method, and DFT calculation results, in which the interaction, binding energies, and transition states were determined. 相似文献
957.
Luciano Medina-Macedo André Eduardo Biscaia de Lacerda Alexandre Magno Sebbenn Juliana Zanetti Ribeiro Carlos Ricardo Soccol Juliana Vitoria Messias Bittencourt 《Conservation Genetics》2016,17(2):413-423
In order to understand the impacts of forest fragmentation on Araucaria angustifolia populations, we evaluated the genetic diversity and mating system using SSR markers and open-pollinated seeds from four populations of varying sizes and spatial isolation, in and around one of the best-conserved Araucaria Forest remnants in Southern Brazil. The four population types of A. angustifolia include: (1) a continuous forest; (2) a physically isolated cluster located 2 km from the continuous forest; (3) an open population in a field located between the cluster and continuous forest; and (4) a fragment on a private property located 5 km from the cluster. Approximately 28 seeds were collected from ten reproductive trees in each population. We found higher amounts of alleles (113) and exclusive alleles (25) in the continuous forest than in the other populations. The multilocus paternity correlation was significantly higher and effective number of pollen donors was significantly lower in the private population, decreasing the diversity and consequently the variance effective size of families sampled from that population. However, despite its isolation from the other studied fragments, the private population had the second highest number of alleles as well as unique alleles from the other populations. Therefore, strategies for A. angustifolia conservation should focus not only on larger populations, such as those found in protected areas, but also include smaller and isolated fragments on private properties as these populations are able to maintain high levels of genetic diversity and functional connectivity between isolated stands across a landscape. 相似文献
958.
Veronika Aleksandrovych Jerzy A. Walocha Krzysztof Gil 《Journal of cellular and molecular medicine》2016,20(6):994-1000
Telocytes (TCs) are a newly discovered type of cell with numerous functions. They have been found in a large variety of organs: heart (endo‐, myo‐, epi‐ and pericardium, myocardial sleeves, heart valves); digestive tract and annex glands (oesophagus, stomach, duodenum, jejunum, liver, gallbladder, salivary gland, exocrine pancreas); respiratory system (trachea and lungs); urinary system (kidney, renal pelvis, ureters, bladder, urethra); female reproductive system (uterus, Fallopian tube, placenta, mammary gland); vasculature (blood vessels, thoracic duct); serous membranes (mesentery and pleura); and other organs (skeletal muscle, meninges and choroid plexus, neuromuscular spindles, fascia lata, skin, eye, prostate, bone marrow). Likewise, TCs are widely distributed in vertebrates (fish, reptiles, birds, mammals, including human). This review summarizes particular features of TCs in the female reproductive system, emphasizing their involvement in physiological and pathophysiological processes. 相似文献
959.
Sarah Mas-y-Mas Marta Barbon Catherine Teyssier Hélène Déméné Jo?o E. Carvalho Louise E. Bird Andrey Lebedev Juliana Fattori Michael Schubert Christian Dumas William Bourguet Albane le Maire 《PloS one》2016,11(11)
Mixed Lineage Leukemia 5 (MLL5) plays a key role in hematopoiesis, spermatogenesis and cell cycle progression. Chromatin binding is ensured by its plant homeodomain (PHD) through a direct interaction with the N-terminus of histone H3 (H3). In addition, MLL5 contains a Su(var)3-9, Enhancer of zeste, Trithorax (SET) domain, a protein module that usually displays histone lysine methyltransferase activity. We report here the crystal structure of the unliganded SET domain of human MLL5 at 2.1 Å resolution. Although it shows most of the canonical features of other SET domains, both the lack of key residues and the presence in the SET-I subdomain of an unusually large loop preclude the interaction of MLL5 SET with its cofactor and substrate. Accordingly, we show that MLL5 is devoid of any in vitro methyltransferase activity on full-length histones and histone H3 peptides. Hence, the three dimensional structure of MLL5 SET domain unveils the structural basis for its lack of methyltransferase activity and suggests a new regulatory mechanism. 相似文献
960.
Nidiane D. R. Prado Soraya S. Pereira Michele P. da Silva Michelle S. S. Morais Anderson M. Kayano Leandro S. Moreira-Dill Marcos B. Luiz Fernando B. Zanchi André L. Fuly Maribel E. F. Huacca Cleberson F. Fernandes Leonardo A. Calderon Juliana P. Zuliani Luiz H. Pereira da Silva Andreimar M. Soares Rodrigo G. Stabeli Carla F. C. Fernandes 《PloS one》2016,11(3)
Antivenoms, produced using animal hyperimmune plasma, remains the standard therapy for snakebites. Although effective against systemic damages, conventional antivenoms have limited efficacy against local tissue damage. Additionally, the hypersensitivity reactions, often elicited by antivenoms, the high costs for animal maintenance, the difficulty of producing homogeneous lots, and the instability of biological products instigate the search for innovative products for antivenom therapy. In this study, camelid antibody fragments (VHH) with specificity to Bothropstoxin I and II (BthTX-I and BthTX-II), two myotoxic phospholipases from Bothrops jararacussu venom, were selected from an immune VHH phage display library. After biopanning, 28 and 6 clones recognized BthTX-I and BthTX-II by ELISA, respectively. Complementarity determining regions (CDRs) and immunoglobulin frameworks (FRs) of 13 VHH-deduced amino acid sequences were identified, as well as the camelid hallmark amino acid substitutions in FR2. Three VHH clones (, KF498607, and KF498608) were capable of recognizing BthTX-I by Western blot and showed affinity constants in the nanomolar range against both toxins. VHHs inhibited the BthTX-II phospholipase A2 activity, and when tested for cross-reactivity, presented specificity to the Bothrops genus in ELISA. Furthermore, two clones ( KC329718 and KC329718) neutralized the myotoxic effects induced by B. jararacussu venom, BthTX-I, BthTX-II, and by a myotoxin from Bothrops brazili venom (MTX-I) in mice. Molecular docking revealed that VHH CDRs are expected to bind the C-terminal of both toxins, essential for myotoxic activity, and to epitopes in the BthTX-II enzymatic cleft. Identified VHHs could be a biotechnological tool to improve the treatment for snake envenomation, an important and neglected world public health problem. KF498607相似文献