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Serena Moruzzi Giuseppe Firrao Cesare Polano Stefano Borselli Alberto Loschi Paolo Ermacora 《Biocontrol Science and Technology》2017,27(8):969-991
In an attempt to select potential biocontrol agents against Pythium spp. and Rhizoctonia spp. root pathogens for use in soilless systems, 12 promising bacteria were selected for further investigations. Sequence analysis of the 16S rRNA gene revealed that three strains belonged to the genus Enterobacter, whereas nine strains belonged to the genus Pseudomonas. In in vitro assays, one strain of Pseudomonas sp., Pf4, closely related to Pseudomonas protegens (formerly Pseudomonas fluorescens), showed noteworthy antagonistic activity against two strains of Pythium aphanidermatum and two strains of Rhizoctonia solani AG 1-IB, with average inhibition of mycelial growth >80%. Strain Pf4 was used for in vivo treatments on lamb’s lettuce against R. solani root rot in small-scale hydroponics. Pf4-treated and untreated plants were daily monitored for symptom development and after two weeks of infection, a significant protective effect of Pf4 against root rot was recorded. The survival and population density of Pf4 on roots were also checked, demonstrating a density above the threshold value of 105?CFU?g?1 of root required for disease suppression. Known loci for the synthesis of antifungal metabolites, detected using PCR, and draft-genome sequencing of Pf4 demonstrated that Pseudomonas sp. Pf4 has the potential to produce an arsenal of secondary metabolites (plt, phl, ofa and fit-rzx gene clusters) very similar to that of the well-known biocontrol P. protegens strain Pf-5. 相似文献
994.
Carla E. Brown Tiffany Kong James McNulty Leonardo DAiuto Kelly Williamson Lora McClain Paolo Piazza Vishwajit L. Nimgaonkar 《Bioorganic & medicinal chemistry letters》2017,27(20):4601-4605
The discovery of antiviral activity of 2,3-disubstituted quinazolinones, prepared by a one-pot, three-component condensation of isatoic anhydride with amines and aldehydes, against Herpes Simplex Virus (HSV)-1 is reported. Sequential iterative synthesis/antiviral assessment allowed structure-activity relationship (SAR) generation revealing synergistic structural features required for potent anti-HSV-1 activity. The most potent derivatives show greater efficacy than acyclovir against acute HSV-1 infections in neurons and minimal toxicity to the host. 相似文献
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996.
Yoan R. Monneau Paolo Rossi Anusarka Bhaumik Chengdong Huang Yajun Jiang Tamjeed Saleh Tao Xie Qiong Xing Charalampos G. Kalodimos 《Journal of biomolecular NMR》2017,69(4):215-227
Selective methyl labeling is an extremely powerful approach to study the structure, dynamics and function of biomolecules by NMR. Despite spectacular progress in the field, such studies remain rather limited in number. One of the main obstacles remains the assignment of the methyl resonances, which is labor intensive and error prone. Typically, NOESY crosspeak patterns are manually correlated to the available crystal structure or an in silico template model of the protein. Here, we propose methyl assignment by graphing inference construct, an exhaustive search algorithm with no peak network definition requirement. In order to overcome the combinatorial problem, the exhaustive search is performed locally, i.e. for a small number of methyls connected through-space according to experimental 3D methyl NOESY data. The local network approach drastically reduces the search space. Only the best local assignments are combined to provide the final output. Assignments that match the data with comparable scores are made available to the user for cross-validation by additional experiments such as methyl-amide NOEs. Several NMR datasets for proteins in the 25–50 kDa range were used during development and for performance evaluation against the manually assigned data. We show that the algorithm is robust, reliable and greatly speeds up the methyl assignment task. 相似文献
997.
HOTAIR role in melanoma progression and its identification in the blood of patients with advanced disease 下载免费PDF全文
998.
Paolo Monaco Laura Bracchini Francisco J. Rodríguez‐Tovar Alfred Uchman Rodolfo Coccioni 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2017,50(1):41-57
About 200 Zoophycos specimens, including 90 specimens studied in detail, have been analysed in the continuous Upper Cretaceous–Lower Miocene pelagic sedimentary type sections of the Gubbio area (the Contessa Highway, Contessa Quarry and Bottaccione sections, Northern Apennines). The sediments are reddish to grey limestones and marls of the Scaglia Group and marls with volcaniclastic deposits of the Bisciaro Formation. The aim was to examine the evolutionary trend of what is probably the most debated trace fossil of all time, from the Upper Cretaceous to Lower Miocene. Despite having been found in beds ranging from the Cambrian to the present, no consensus has been reached regarding mode of construction, tracemaker or ethological explanation for Zoophycos. Four Zoophycos morphotypes are recognized at Gubbio showing variations of major and minor lamellae, apex, lobes and whorls: the Cretaceous–Eocene cone‐shaped type 1, the Upper Eocene–Middle Oligocene helicoidal type 2, the Oligocene lobate type 3 and the Upper Oligocene–Lower Miocene flat type 4. The very high ichnodensity in some beds (hundreds of specimens in discrete levels of the Bisciaro Formation, now destroyed by quarrying) seems to find explanation in abnormal concentrations of phytodetritus and organic matter on the seafloor in some periods. This very high abundance in discrete levels reflects a change in sedimentation and seafloor conditions at pre‐flysch deposition. Due to such high ichnodensity, many adjacent specimens display deformed outer margins. Taphonomic analysis shows a variation of whorls, laminae and U‐shaped lobes, reflecting ontogenetic development of the tracemaker(s) (?sipunculid worms). 相似文献
999.
Giovanni Battista Conselvan Diego Pizzeghello Ornella Francioso Michele Di Foggia Serenella Nardi Paolo Carletti 《Plant and Soil》2017,420(1-2):119-134
Background and aims
Biostimulants are natural compounds that enhance plant growth and plant nutrient use efficiency. In this study, biostimulant effects of humic substances (HS) extracted from leonardites were analysed on the metabolism of maize plants grown in hydroponic conditions.Methods
HS extracted from four leonardites were tested for their auxin-like and gibberellin-like activities. Then, 11 day old maize seedlings were treated for 48 h with five concentrations (0, 0.1, 0.5, 1, and 10 mg C L?1) of HS. After sampling, root growth and morphology, glutamine synthetase (GS) activity, glutamate synthase (GOGAT) activity, total protein content, soluble sugars content, phenylalanine ammonia-lyase (PAL) activity, soluble phenols, and free phenolic acids were analysed.Results
HS from leonardites had similar spectroscopic pattern, with small differences. The HS from the South Dakota lignite (HS_USA) had more carboxylic groups, whereas the three from Turkish mines had more aromatic and aliphatic structures. HS_USA best enhanced total root growth, root surface area, and proliferation of secondary roots. Plant nutrient use efficiency was enhanced by HS_4, HS_USA and HS_B, with increment of GS and GOGAT enzymes activity and total protein production. HS stimulated also PAL enzyme activity, followed by a higher production of total soluble phenols, p-hydroxybenzoic acid, p-coumarilic acid, and chlorogenic acid.Conclusion
This study found that, although the activity of the HS depended on the origin of the leonardite, these compounds can be attributed to the biostimulant products, eliciting plant growth, nitrogen metabolism, and accumulation of phenolic substances.1000.
Baldi Paolo Moser Mirko Brilli Matteo Vrhovsek Urska Pindo Massimo Si-Ammour Azeddine 《Planta》2017,245(5):1021-1035
Planta - A coordinated regulation of different branches of the flavonoid pathway was highlighted that may contribute to elucidate the role of this important class of compounds during the early... 相似文献