Search results for "Ribosomal"
showing 10 items of 851 documents
Pythium contiguanum nomen novum (syn. Pythium dreschleri Paul), its antagonism to Botrytis cinerea, ITS1 region of its nuclear ribosomal DNA, and its…
2000
Pythium drechsleri Paul was described as a new species from soil samples taken in a salt-marsh of Arzew, Algeria [Paul, B. (1988) Une nouvelle espece de Pythium isolee d'une saline de l'ouest Algerien. Cryptogam. Mycol. 9, 325-333]. The name of the fungus, P. drechsleri, is a nomen invalidum, as it is a later homonym of P. drechsleri Rajgopalan and Ramakrishnan [Rajagopalan, S. and Ramakrishnan, K. (1971) Phycomycetes in agricultural soils with special reference to the Pythiaceae. Madras Univ. J. Sect. B 37,38, 100-117]. A new name, Pythium contiguanum is now being given to P. drechsleri Paul. This species is characterised by its contiguous inflated type of sporangia, smooth-walled oogonia …
Inorganic phosphate is a trigger factor for Microbispora sp. ATCC-PTA-5024 growth and NAI-107 production
2014
Background NAI-107, produced by the actinomycete Microbispora sp. ATCC-PTA-5024, is a promising lantibiotic active against Gram-positive bacteria and currently in late preclinical-phase. Lantibiotics (lanthionine-containing antibiotics) are ribosomally synthesized and post-translationally modified peptides (RiPPs), encoded by structural genes as precursor peptides. The biosynthesis of biologically active compounds is developmentally controlled and it depends upon a variety of environmental stimuli and conditions. Inorganic phosphate (Pi) usually negatively regulates biologically-active molecule production in Actinomycetes, while it has been reported to have a positive control on lantibiotic…
Isolation of Gram-positive n-alkane degraders from a hydrocarbon-contaminated Mediterranean shoreline.
2007
Aims: To investigate the petroleum hydrocarbon (HC)-degrading potential of indigenous micro-organisms in a sandy Mediterranean coast, accidentally contaminated with petroleum-derived HCs. Methods and Results: Using culturable methods, a population of Gram-positive n-alkane degraders was detected in the contaminated soil. Five isolates, identified as one Nocardia, two Rhodococcus and two Gordonia strains, were able to degrade medium- and long-chain n-alkanes up to C36 as assessed by growth assays and gas chromatography-mass spectrometry analysis. Diverging alkane hydroxylase-encoding genes (alkB) were detected by PCR, using degenerated primers, in all the strains; multiple sequences were obt…
Molecular phylogeny of the spider family Sparassidae with focus on the genus Eusparassus and notes on the RTA-clade and ‘Laterigradae’
2013
The phylogeny of the spider family Sparassidae is comprehensively investigated using four molecular markers (mitochondrial COI and 16S; nuclear H3 and 28S). Sparassidae was recovered as monophyletic and as most basal group within the RTA-clade. The higher-level clade Dionycha was not but monophyly of RTA-clade was supported. No affiliation of Sparassidae to other members of the 'Laterigradae' (Philodromidae, Selenopidae and Thomisidae) was observed, and the crab-like posture of this group assumed a result of convergent evolution. Only Philodromidae and Selenopidae were found members of a supported clade, but together with Salticidae and Corinnidae, while Thomisidae was nested within the hig…
Development of a qPCR assay for specific quantification of Botrytis cinerea on grapes
2010
The aim of this study was to develop a system for rapid and accurate real-time quantitative PCR (qPCR) identification and quantification of Botrytis cinerea , one of the major pathogens present on grapes. The intergenic spacer (IGS) region of the nuclear ribosomal DNA was used to specifically detect and quantify B. cinerea . A standard curve was established to quantify this fungus. The qPCR reaction was based on the simultaneous detection of a specific IGS sequence and also contained an internal amplification control to compensate for variations in DNA extraction and the various compounds from grapes that inhibit PCR. In these conditions, the assay had high efficiency (97%), and the limit o…
Validation and application of a PCR primer set to quantify fungal communities in the soil environment by real-time quantitative PCR
2011
Fungi constitute an important group in soil biological diversity and functioning. However, characterization and knowledge of fungal communities is hampered because few primer sets are available to quantify fungal abundance by real-time quantitative PCR (real-time Q-PCR). The aim in this study was to quantify fungal abundance in soils by incorporating, into a real-time Q-PCR using the SYBRGreen (R) method, a primer set already used to study the genetic structure of soil fungal communities. To satisfy the real-time Q-PCR requirements to enhance the accuracy and reproducibility of the detection technique, this study focused on the 18S rRNA gene conserved regions. These regions are little affec…
Antifungal activity improved by coproduction of cyclodextrins and anabaenolysins in Cyanobacteria
2015
Department of Chemistry, Nanoscience Center, University of Jyväskylä, FI-40014, Jyväskylä, Finland Cyclodextrins are cyclic oligosaccharides widely used in the pharmaceutical industry to improve drug delivery and to increase the solubility of hydrophobic compounds. Anabaenolysins are lipopeptides produced by cyanobacteria with potent lytic activity in cholesterolcontaining membranes. Here, we identified the 23- To 24-kb gene clusters responsible for the production of the lipopeptide anabaenolysin. The hybrid nonribosomal peptide synthetase and polyketide synthase biosynthetic gene cluster is encoded in the genomes of three anabaenolysin-producing strains of Anabaena.We detected previously u…
Extremophilic microbial communities on photovoltaic panel surfaces: a two‐year study
2020
Solar panel surfaces can be colonized by microorganisms adapted to desiccation, temperature fluctuations and solar radiation. Although the taxonomic and functional composition of these communities has been studied, the microbial colonization process remains unclear. In the present work, we have monitored this microbial colonization process during 24 months by performing weekly measurements of the photovoltaic efficiency, carrying out 16S rRNA gene high‐throughput sequencing, and studying the effect of antimicrobial compounds on the composition of the microbial biocenosis. This is the first time a long‐term study of the colonization process of solar panels has been performed, and our results…
Baseline Gut Microbiota Composition Is Associated With Schistosoma mansoni Infection Burden in Rodent Models
2020
In spite of growing evidence supporting the occurrence of complex interactions between Schistosoma and gut bacteria in mice and humans, no data is yet available on whether worm-mediated changes in microbiota composition are dependent on the baseline gut microbial profile of the vertebrate host. In addition, the impact of such changes on the susceptibility to, and pathophysiology of, schistosomiasis remains largely unexplored. In this study, mice colonized with gut microbial populations from a human donor (HMA mice), as well as microbiota-wild type (WT) animals, were infected with Schistosoma mansoni, and alterations of their gut microbial profiles at 50 days post-infection were compared to …
Solving a Bloody Mess: B-Vitamin Independent Metabolic Convergence among Gammaproteobacterial Obligate Endosymbionts from Blood-Feeding Arthropods an…
2015
Endosymbiosis is a common phenomenon in nature, especially between bacteria and insects, whose typically unbalanced diets are usually complemented by their obligate endosymbionts. While much interest and focus has been directed toward phloem-feeders like aphids and mealybugs, blood-feeders such as the Lone star tick (Amblyomma americanum), Glossina flies, and the human body louse (Pediculus humanus corporis) depend on obligate endosymbionts which complement their B-vitamin-deficient diets, and thus are required for growth and survival. Glossiphoniid leeches have also been found to harbor distinct endosymbionts housed in specialized organs. Here, we present the genome of the bacterial endosy…