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21.
Endophytic bacteria of Sphagnum mosses as promising objects of agricultural microbiology 总被引:1,自引:0,他引:1
A. V. Shcherbakov A. V. Bragina E. Yu. Kuzmina Christian Berg A. N. Muntyan N. M. Makarova N. V. Malfanova Massimiliano Cardinale Gabriele Berg V. K. Chebotar I. A. Tikhonovich 《Microbiology》2013,82(3):306-315
Sphagnum mosses serve as a unique habitat for microorganisms, which play an important role both for the host plants and the peatland ecosystems. The aim of the present study was to isolate endophytic bacteria from the tissues of Sphagnum mosses and to screen them for strains promising for further application in agricultural microbiology. About 50 samples of Sphagnum fallax (H. Klinggr.) H. Klinggr. and Sphagnum magellanicum Brid. were collected in the Austrian Alps and the Lenindgrad Region of Russia in 2009–2010. Endophytic bacteria were detected inside the moss plants using fluorescent in situ hybridization (FISH) followed by confocal laser scanning microscopy (CLSM). Altogether, 283 isolates were obtained by cultivation on the nutrient media. Examination of the isolates for the antagonistic activity revealed that more than 50% of them could suppress the growth of phytopathogenic and toxigenic fungi. More than 30% of isolates showed some antagonistic activity against microbial phytopathogens. The isolated strains could colonize crops and promote their growth. Molecular-genetic identification coupled with physiological/biochemical characterization showed that the dominant endophytic groups belonged to the genera Burkholderia, Pseudomonas, Flavobacterium, Serratia and Collimonas. The isolated endophytes were shown to be promising objects for the development of effective growth-promoting and protective microbiological preparations to be used in agriculture. 相似文献
22.
Paolo Barghini Deborah Moscatelli Anna Maria Vittoria Garzillo Silvia Crognale Massimiliano Fenice 《Enzyme and microbial technology》2013
The Antarctic fungus Lecanicillium muscarium CCFEE-5003 was preliminary cultivated in shaken flasks to check its chitinase production on rough shrimp and crab wastes. Production on shrimp shells was much higher than that on crab shells (104.6 ± 9.3 and 48.6 ± 3.1 U/L, respectively). For possible industrial applications, bioprocess optimization was studied on shrimp shells in bioreactor using RSM to state best conditions of pH and substrate concentration. Optimization improved the production by 137% (243.6 ± 17.3). Two chitinolytic enzymes (CHI1 and CHI2) were purified and characterized. CHI1 (MW ca. 61 kDa) showed optima at pH 5.5 and 45 °C while CHI2 (MW ca. 25 kDa) optima were at pH 4.5 and 40 °C. Both enzymes maintained high activity levels at 5 °C and were inhibited by Fe++, Hg++ and Cu++. CHI2 was strongly allosamidin-sensitive. Both proteins were N-acetyl-hexosaminidases (E.C. 3.2.1.52) but showed different roles in chitin hydrolysis: CHI1 could be defined as “chitobiase” while CHI2 revealed a main “eso-chitinase” activity. 相似文献
23.
Isabella Daidone Massimiliano Aschi Maria Patamia Argante Bozzi Raffaele Petruzzelli 《Biopolymers》2013,99(1):47-54
Obtustatin and Lebestatin are lysine‐threonine‐serine (KTS)‐disintegrins, which are a family of low molecular weight polypeptides present in many viperidae venoms and are potent and specific inhibitors of collagen‐binding integrins. The integrin binding loop, harboring the 21KTS23 motif, and the C‐terminal tail are known to be responsible for the selective binding to the α1β1 integrin. Despite a very high sequence homology (only two mutations are present in Lebestatin relative to Obtustatin, namely R24L and S38L), Lebestatin exhibits a higher inhibitory effect than Obtustatin on cell adhesion and cell migration to collagens I and IV. Here we show, by means of molecular dynamics simulations of the two polypeptides in aqueous solution, that Lebestatin possesses a higher flexibility of the C‐terminal tail and a greater solvent accessibility of the integrin binding loop than Obtustatin. It may be hypothesized that these properties may contribute to the higher binding‐affinity of Lebestatin to its biological partner. © 2012 Wiley Periodicals, Inc. 相似文献
24.
Fabio Lapenta Alejandro Montón Silva Renato Brandimarti Massimiliano Lanzi Fabio Lino Gratani Perceval Vellosillo Gonzalez Sofia Perticarari Alejandro Hochkoeppler 《PloS one》2016,11(4)
DNA Polymerases generate pyrophosphate every time they catalyze a step of DNA elongation. This elongation reaction is generally believed as thermodynamically favoured by the hydrolysis of pyrophosphate, catalyzed by inorganic pyrophosphatases. However, the specific action of inorganic pyrophosphatases coupled to DNA replication in vivo was never demonstrated. Here we show that the Polymerase-Histidinol-Phosphatase (PHP) domain of Escherichia coli DNA Polymerase III α subunit features pyrophosphatase activity. We also show that this activity is inhibited by fluoride, as commonly observed for inorganic pyrophosphatases, and we identified 3 amino acids of the PHP active site. Remarkably, E. coli cells expressing variants of these catalytic residues of α subunit feature aberrant phenotypes, poor viability, and are subject to high mutation frequencies. Our findings indicate that DNA Polymerases can couple DNA elongation and pyrophosphate hydrolysis, providing a mechanism for the control of DNA extension rate, and suggest a promising target for novel antibiotics. 相似文献
25.
Manfredi Allegri Massimiliano G. Bianchi Martina Chiu Julia Varet Anna L. Costa Simona Ortelli Magda Blosi Ovidio Bussolati Craig A. Poland Enrico Bergamaschi 《PloS one》2016,11(3)
Titanium dioxide (TiO2) nanofibres are a novel fibrous nanomaterial with increasing applications in a variety of fields. While the biological effects of TiO2 nanoparticles have been extensively studied, the toxicological characterization of TiO2 nanofibres is far from being complete. In this study, we evaluated the toxicity of commercially available anatase TiO2 nanofibres using TiO2 nanoparticles (NP) and crocidolite asbestos as non-fibrous or fibrous benchmark materials. The evaluated endpoints were cell viability, haemolysis, macrophage activation, trans-epithelial electrical resistance (an indicator of the epithelial barrier competence), ROS production and oxidative stress as well as the morphology of exposed cells. The results showed that TiO2 nanofibres caused a cell-specific, dose-dependent decrease of cell viability, with larger effects on alveolar epithelial cells than on macrophages. The observed effects were comparable to those of crocidolite, while TiO2 NP did not decrease cell viability. TiO2 nanofibres were also found endowed with a marked haemolytic activity, at levels significantly higher than those observed with TiO2 nanoparticles or crocidolite. Moreover, TiO2 nanofibres and crocidolite, but not TiO2 nanoparticles, caused a significant decrease of the trans-epithelial electrical resistance of airway cell monolayers. SEM images demonstrated that the interaction with nanofibres and crocidolite caused cell shape perturbation with the longest fibres incompletely or not phagocytosed. The expression of several pro-inflammatory markers, such as NO production and the induction of Nos2 and Ptgs2, was significantly increased by TiO2 nanofibres, as well as by TiO2 nanoparticles and crocidolite. This study indicates that TiO2 nanofibres had significant toxic effects and, for most endpoints with the exception of pro-inflammatory changes, are more bio-active than TiO2 nanoparticles, showing the relevance of shape in determining the toxicity of nanomaterials. Given that several toxic effects of TiO2 nanofibres appear comparable to those observed with crocidolite, the possibility that they exert length dependent toxicity in vivo seems worthy of further investigation. 相似文献
26.
Massimiliano Carnabuci Giulia Schiavon Michela Bellingeri Fulvio Fossa Chiara Paoli Paolo Vassallo Guido Gnone 《Population Ecology》2016,58(2):249-264
The bottlenose dolphin (Tursiops truncatus Montagu, 1821) is a regularly observed species in the Mediterranean Sea, but its network organization has never been investigated on a large scale. We described the network macrostructure of the bottlenose dolphin (meta)population inhabiting the Pelagos Sanctuary (a wide protected area located in the north-western portion of the Mediterranean basin) and we analysed its connectivity in relation to the landscape traits. We pooled effort and sighting data collected by 13 different research institutions operating within the Pelagos Sanctuary from 1994 to 2011 to examine the distribution of bottlenose dolphins in the Pelagos study area and then we applied a social network analysis, investigating the association patterns of the photo-identified dolphins (806 individuals in 605 sightings). The bottlenose dolphin (meta)population inhabiting the Pelagos Sanctuary is clustered in discrete units whose borders coincide with habitat breakages. This complex structure seems to be shaped by the geo-morphological and ecological features of the landscape, through a mechanism of local specialization of the resident dolphins. Five distinct clusters were identified in the (meta)population and two of them were solid enough to be further investigated and compared. Significant differences were found in the network parameters, suggesting a different social organization of the clusters, possibly as a consequence of the different local specialization. 相似文献
27.
Gisela M. Via do Pico Yanina J. Prez María B. Angulo Massimiliano Dematteis 《植物分类学报:英文版》2019,57(5):451-467
Understanding speciation and biodiversity patterns in plants requires knowledge of the general role of climate in allowing polyploids to escape competition and persist with their diploid progenitors. This is a particularly interesting issue in widespread species that present multiple ploidy levels and occur across a heterogeneous environment. Chrysolaena (Vernonieae, Asteraceae) is a cytogenetically very diverse genus, with significant interspecific and intraspecific ploidy level variation and with continuous distribution across South America. No previous studies have summarized chromosome count data of Chrysolaena or addressed the cytogeography of the genus. Ploidy level of Chrysolaena species was determined by chromosome counting during mitosis and/or meiosis; the geographic distribution of cytotypes was examined and the correlations between the distribution of particular cytotypes and current ecological conditions were evaluated. A total of 43 new chromosome counts and five ploidy levels (2x, 4x, 6x, 7x, 8x) were reported. The chromosome number of C. cordifolia (2n = 7x = 70) and a new cytotype for C. propinqua var. canescens (2n = 4x = 40) are reported for the first time. Three geographic areas with high diversity of cytotypes and species were detected. The results obtained do not suggest a clear distribution pattern that depends on climatic factors for Chrysolaena populations. However, a geographic pattern was identified in the distribution of ploidy levels, with diploid species presenting a more restricted distribution than polyploid species. 相似文献
28.
Francesca Giampieri Md Soriful Islam Stefania Greco Massimiliano Gasparrini Tamara Y. Forbes Hernandez Giovanni Delli Carpini Stefano Raffaele Giannubilo Andrea Ciavattini Bruno Mezzetti Luca Mazzoni Franco Capocasa Mario Castellucci Maurizio Battino Pasquapina Ciarmela 《Journal of cellular physiology》2019,234(5):7622-7633
Uterine leiom yomas are benign tumors highly prevalent in reproductive women. In thecurrent study, initially, we aimed to screen five different strawberry cultivars (Alba, Clery, Portola, Tecla, and Romina) to identify efficient cultivars in terms of phytochemical characterization and biological properties by measuring phenolic and anthocyanin content as well as antioxidant capacity, and by measuring apoptotic rate and reactive oxygen species (ROS) production in uterine leiomyoma cells. Next, we focused on the most efficient ones, cultivar Alba (A) and Romina (R) as well as Romina anthocyanin (RA) fraction for their ability to regulate oxidative phosphorylation (oxygen consumption rate [OCR]) glycolysis (extracellular acidification rate [ECAR]), and also fibrosis. Leiomyoma and myometrial cells were treated with a methanolic extract of A and R (250 μg/ml) or with RA (50 μg/ml) for 48 hr to measure OCR and ECAR, as well as gene expression associated with fibrosis. In the leiomyoma cells, RA was more effective in inducing apoptosis and increasing intracellular ROS levels, followed by R and A. In myometrial cells, all strawberry treatments increased the cellular viability and decreased ROS concentrations. Leiomyoma cells showed also a significant decrease in ECAR, especially after RA treatment, while OCR was slightly increased in both myometrial and leiomyoma cells. R and RA treatment significantly decreased collagen 1A1, fibronectin, versican, and activin A messenger RNA expression in leiomyoma cells. In conclusion, this study suggests that Romina, or its anthocyanin fraction, can be developed as a therapeutic and/or preventive agent for uterine leiomyomas, confirming the healthy effects exerted by these fruits and their bioactive compounds. 相似文献
29.
Rita Aldini Matteo Micucci Monica Cevenini Romana Fato Christian Bergamini Cristina Nanni Massimiliano Cont Cecilia Camborata Silvia Spinozzi Marco Montagnani Giulia Roda Antonia D'Errico-Grigioni Francesca Rosini Aldo Roda Giuseppe Mazzella Alberto Chiarini Roberta Budriesi 《PloS one》2014,9(9)
Phytosterols, besides hypocholesterolemic effect, present anti-inflammatory properties. Little information is available about their efficacy in Inflammatory Bowel Disease (IBD). Therefore, we have evaluated the effect of a mixture of phytosterols on prevention/induction/remission in a murine experimental model of colitis. Phytosterols were administered x os before, during and after colitis induction with Dextran Sodium Sulfate (DSS) in mice. Disease Activity Index (DAI), colon length, histopathology score, 18F-FDG microPET, oxidative stress in the intestinal tissue (ileum and colon) and gallbladder ileum and colon spontaneous and carbachol (CCh) induced motility, plasma lipids and plasma, liver and biliary bile acids (BA) were evaluated. A similar longitudinal study was performed in a DSS colitis control group. Mice treated with DSS developed severe colitis as shown by DAI, colon length, histopathology score, 18F-FDG microPET, oxidative stress. Both spontaneous and induced ileal and colonic motility were severely disturbed. The same was observed with gallbladder. DSS colitis resulted in an increase in plasma cholesterol, and a modification of the BA pattern. Phytosterols feeding did not prevent colitis onset but significantly reduced the severity of the disease and improved clinical and histological remission. It had strong antioxidant effects, almost restored colon, ileal and gallbladder motility. Plasmatic levels of cholesterol were also reduced. DSS induced a modification in the BA pattern consistent with an increase in the intestinal BA deconjugating bacteria, prevented by phytosterols. Phytosterols seem a potential nutraceutical tool for gastrointestinal inflammatory diseases, combining metabolic systematic and local anti-inflammatory effects. 相似文献