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981.
Grasielle Pereira Jannuzzi José Roberto Fogaça de Almeida Suelen Silvana dos Santos Sandro Rogério de Almeida Karen Spadari Ferreira 《Mycopathologia》2018,183(5):739-749
The Notch signaling pathway participates in several cellular functional aspects. This signaling has an important role in targeting both DC maturation and DC-mediated T cell responses. Thus, it is essential to investigate the influence of this signaling pathway in the role played by DCs in the pathogenesis of experimental paracoccidioidomycosis. This disease is a granulomatous and systemic mycosis that mainly affects lung tissue and can spread to any other organ and system. In this study, we demonstrated that bone marrow-derived DCs infected with yeasts from Paracoccidioides brasiliensis strain 18 performed efficiently their maturation after the activation of Notch signaling, with an increase in CD80, CD86, CCR7, and CD40 expression and the release of cytokines such as IL-6 and TNF-α. We observed that the inhibition of the γ-secretase DAPT impaired the proliferation of T cells induced by DC stimulation. In conclusion, our data suggest that Notch signaling contributes effectively to the maturation of DCs and the DC-mediated activation of the T cell response in P. brasiliensis infections. 相似文献
982.
983.
Érica Barbosa Felestrino Izadora Tabuso Vieira Washington Luiz Caneschi Isabella Ferreira Cordeiro Renata de Almeida Barbosa Assis Camila Gracyelle de Carvalho Lemes Natasha Peixoto Fonseca Angélica Bianchini Sanchez Juan Carlos Caicedo Cepeda Jesus Aparecido Ferro Camila Carrião Machado Garcia Flávio Fonseca do Carmo Luciana Hiromi Yoshino Kamino Leandro Marcio Moreira 《World journal of microbiology & biotechnology》2018,34(10):156
Microorganisms associated with plants have a great biotechnological potential, but investigations of these microorganisms associated with native plants in peculiar environments has been incipient. The objective of this study was to analyze the plant growth-promoting bacteria potential of cultivable bacteria associated with rare plants from the ferruginous rocky fields of the Brazilian Iron Quadrangle. The roots and rhizospheres of nine endemic plants species and samples of a root found in a lateritiric duricrust (canga) cave were collected, the culturable bacteria isolated and prospected for distinct biotechnological and ecological potentials. Out of the 148 isolates obtained, 8 (5.4%) showed potential to promote plant growth, whereas 4 (2.7%) isolates acted as biocontrol agents against Xanthomonas citri pathotype A (Xac306), reducing the cancrotic lesions by more than 60% when co-inoculated with this phytopathogen in Citrus sinensis plants. Moreover, other 4 (2.7%) isolates were classified as potential bioremediation agents, being able to withstand high concentrations of arsenite (5 mM As3+) and arsenate (800 mM As5+), by removing up to 35% and 15% of this metalloid in solution, respectively. These same four isolates had a positive influence on the growth of both the roots and the aerial parts when inoculated with tomato seeds in the soil contaminated with arsenic. This is the first time that an investigation highlights the potentialities of bacteria associated with rare plants of ferruginous rocky fields as a reservoir of microbiota of biotechnological and ecological interest, highlighting the importance of conservation of this area that is undergoing intense anthropic activity. 相似文献
Graphical abstract
984.
A. Braga P. Ferreira J. Oliveira I. Rocha N. Faria 《World journal of microbiology & biotechnology》2018,34(8):122
The polyphenol resveratrol (3,5,4′-trihydroxystilbene) is a well-known plant secondary metabolite, commonly used as a medical ingredient and a nutritional supplement. Due to its health-promoting properties, the demand for resveratrol is expected to continue growing. This stilbene can be found in different plants, including grapes, berries (blackberries, blueberries and raspberries), peanuts and their derived food products, such as wine and juice. The commercially available resveratrol is usually extracted from plants, however this procedure has several drawbacks such as low concentration of the product of interest, seasonal variation, risk of plant diseases and product stability. Alternative production processes are being developed to enable the biotechnological production of resveratrol by genetically engineering several microbial hosts, such as Escherichia coli, Corynebacterium glutamicum, Lactococcus lactis, among others. However, these bacterial species are not able to naturally synthetize resveratrol and therefore genetic modifications have been performed. The application of emerging metabolic engineering offers new possibilities for strain and process optimization. This mini-review will discuss the recent progress on resveratrol biosynthesis in engineered bacteria, with a special focus on the metabolic engineering modifications, as well as the optimization of the production process. These strategies offer new tools to overcome the limitations and challenges for microbial production of resveratrol in industry. 相似文献
985.
Maria L. Ferreira Silvana A. Ramirez Diana L. Vullo 《World journal of microbiology & biotechnology》2018,34(9):134
Siderophores are low-molecular weight ligands secreted by bacteria as a survival strategy in Fe(III)-lacking environments. They bind not only Fe(III), but Co(II), Zn(II), Mn(II), Ni(II), Ga(III) as a detoxification alternative. The synthesis, purification and characterization of siderophores produced by Pseudomonas veronii 2E were evaluated to be applied in future environmental technologies. Optimal production was obtained in Fe(III)-free M9-succinate at 25 °C, 40 h and pH 6.9. Siderophores were chemically characterized as hydroxamate and catechol mixed-type. Spectroscopic analysis indicated their belonging to the pyoverdine family, behaving as ligand to Cd(II), Zn(II), Cu(II), Ni(II) and Cr(III), which promoted siderophoregenesis during growth. Siderophore-Cd(II) complexation was studied by electrochemical monitored titration revealing one family of moderate-strength binding sites. Mass spectral analysis evidenced the secretion of a variety of molecules (molecular mass ca.1200 u). Non pathogenic Pseudomonas veronii 2E siderophores represent a safe alternative for the concrete application of environmental technologies and clinical procedures. 相似文献
986.
Jéssica Fernanda da Silva Thaise Rosa da Silva Indra Elena Costa Escobar Ana Carla Resende Fraiz Jonnathan Whiny Moraes dos Santos Tailane Ribeiro do Nascimento João Marcos Rodrigues dos Santos Samuel James Windsor Peters Roseli Freire de Melo Diana Signor Paulo Ivan Fernandes-Júnior 《World journal of microbiology & biotechnology》2018,34(12):186
Sorghum [Sorghum bicolor (L.) Moench] is a multipurpose grass cultivated in drylands due to its adaptation to drought. However the characteristics of sorghum-associated bacteria are not known in the Brazilian drylands. The aim of this study was to isolate and evaluate the plant growth promotion potential bacteria from field-grown sorghum under two irrigation and manure application levels in a Brazilian semi-arid reagion. Sorghum was irrigated with 3 or 1 mm day?1 and fertilized or not with liquid goat manure. Bacteria were obtained from surface-disinfected roots applying two nitrogen-free semi-solid media. The bacteria were evaluated for the presence of nifH gene, 16S rRNA sequences, calcium-phosphate solubilization, production of auxins and siderophores and for sorghum growth promotion. We obtained 20 out of 24 positive bacteria for nifH. The isolates were classified as in six different genera. All isolates produced auxins “in vitro”, six bacteria produced siderophores and three Enterobacteriaceae solubilized calcium-phosphate. At least ten bacteria resulted in the increased total N content in the sorghum shoots, comparable to fertilization with 50 mg N plant?1 week?1 and to inoculation with Azospirillum brasilense Ab-V5. Enterobacter sp. ESA 57 was the best sorghum plant-growth promoting bacteria isolated in this study. 相似文献
987.
Emerson?R.?PansarinEmail author Pedro?J.?Bergamo Lucenilda?J.?C.?Ferraz Silvia?R.?M.?Pedro Alessandro?W.?C.?Ferreira 《Plant Systematics and Evolution》2018,304(6):793-806
Members of Oncidiinae are widely known for their interactions with oil-collecting bees that explore lipophilic secretions on flowers. They may also be pollinated through food deception and the offering of nectar. Although data on breeding systems are available for many Oncidiinae orchids, little is known about the reproductive strategies in Rodriguezia, a neotropical genus of ca. 55 species. In this paper, we explore the reproductive biology of two species of Rodriguezia with distinctive morphologies: R. decora and R. lanceolata. Floral features, spectral reflectance, pollinators and pollination mechanisms, and breeding systems were studied. Both species are scentless and produce nectar as a reward. Floral nectar is secreted by a gland at the base of the labellum and stored into the sepaline spur. Rodriguezia decora reflects mainly in the blue and red regions of the light spectrum, while R. lanceolata reflects in the red region. Rodriguezia decora is exclusively visited and pollinated by butterflies, while Trochilidae hummingbirds are the pollinators of R. lanceolata. Pollinaria attach to the upper third of the proboscis of butterflies (R. decora), and to the bill of hummingbirds (R. lanceolata), during the collection of nectar from the spur. Both Rodriguezia species are self-sterile. Flower features and floral reflectance support the occurrence of psychophily in R. decora and ornithophily in R. lanceolata. 相似文献
988.
Camille?Ferreira?Maia Breno?Ricardo?Serr?o da?Silva Allan?Klynger da?Silva?LobatoEmail authorView authors OrcID profile 《Journal of Plant Growth Regulation》2018,37(4):1099-1112
Growth and development are vital processes in the life cycles of plants. Brassinosteroids (BRs) are steroids that when exogenously applied can regulate several biological responses. The aim of this research was to investigate the possible interferences caused by the exogenous application of BR on growth and metabolism using two genotypes of the DWARF gene, MT-d and MT-D, that are BR-deficient and BR-efficient, respectively. The experiment had four treatments with two genotypes (BR-efficient and BR-deficient) and two levels of brassinosteroids (0 and 100 nM BR, described as ??BR and +?BR, respectively). This study revealed that the exogenous application of BR promoted improvement in growth, inducing increases in all variables of both genotypes evaluated. In general, BR-deficient plants sprayed with BR had effects more intense, confirming the benefits of this steroid on photosynthetic apparatus and gas exchange. The changes in the anatomical characteristics of the leaf are related to the contribution of BR on the influx and consequent fixation of CO2. In addition, modifications related to root anatomy occurred as a result of the BR action with the purpose of increasing the root protection and absorption of water and nutrients. Increases in photosynthetic pigments suggest that the role of BR is linked with chlorophyll biosynthesis and the maintenance of chloroplast integrity, resulting from associations with the increases found in the activities of antioxidant enzymes that modulate the accumulation of reactive oxygen species. 相似文献
989.
Transcriptome response of the foundation plant Spartina alterniflora to the Deepwater Horizon oil spill
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990.
Diogo Gama Caetano Fernanda Heloise Côrtes Gonzalo Bello Sylvia Lopes Maia Teixeira Brenda Hoagland Beatriz Grinsztejn Valdilea Gonçalves Veloso Monick Lindenmeyer Guimarães Mariza Gonçalves Morgado 《Retrovirology》2018,15(1):62