Search results for "PHYLOGENE"
showing 10 items of 1189 documents
The evolutionary history of HSA7/16 synteny in vertebrates: a critical interpretation of comparative cytogenetic and genome sequence data
2013
The current work is an in silico study of data from previous publications and genome browsers, on the origin of the human synteny HSA7a/16p. The molecular composition of the chromosomal segments identified as HSA7a/16 and 7b (free or differently associated) is not yet clear. This means that a syntenic association 7/16, which can be detected by an in situ hybridization (FISH) method in different taxa, may not necessarily correspond to those of the same association in different lineages. In silico research, together with comparative cytogenetics, have been applied in order to define the composition of the 7/16 syntenic association. These results allow a confident reconstruction of the synteni…
Molecular Phylogenetic Analyses in Court Trials
2010
Molecular phylogenetics allows reconstructing of the genealogy and evolutionary history of organisms from information on their nucleotide or amino acid sequences. When sequences are derived from very fast evolving organisms, such as ribonucleic acid (RNA) viruses, changes accumulate in a few days or weeks, thus allowing the reconstruction of very recent evolutionary events in the history of these populations. One such event is the transmission of one of these viruses, for instance human immunodeficiency virus (HIV) or hepatitis C virus (HCV), from an infected person to another. This occasionally results in a legal demand seeking for compensation and/or punishment for the transmitter. Hence,…
Deciphering the role of insertion sequences in the evolution of bacterial epidemic pathogens with panISa software
2020
Next-generation sequencing (NGS) is now widely used in microbiology to explore genome evolution and the structure of pathogen outbreaks. Bioinformatics pipelines readily detect single-nucleotide polymorphisms or short indels. However, bacterial genomes also evolve through the action of small transposable elements called insertion sequences (ISs), which are difficult to detect due to their short length and multiple repetitions throughout the genome. We designed panISa software for the ab initio detection of IS insertions in the genomes of prokaryotes. PanISa has been released as open source software (GPL3) available from https://github.com/bvalot/panISa. In this study, we assessed the utilit…
Wickerhamomyces sylviae f.a., sp. nov., an ascomycetous yeast species isolated from migratory birds.
2013
In the present work, we investigated the phylogenetic position and phenotypic characteristics of eight yeast isolates collected from migratory birds on the island of Ustica, Italy. A phylogenetic analysis based on the D1/D2 region of the large-subunit rRNA gene showed that all isolates clustered as a single separate lineage within the Wickerhamomyces clade. They exhibited distinct morphological and physiological characteristics and were clearly separated from their closest relatives, Wickerhamomyces lynferdii, Wickerhamomyces anomalus and Wickerhamomyces subpelliculosus, in blastn searches. On the basis of the isolation source, physiological features and molecular strain typing carried out …
Authentication and identification of Saccharomyces cerevisiae‘flor’ yeast races involved in sherry ageing
2004
Yeasts involved in velum formation during biological ageing of sherry wine have to date been classified into four races of Saccharomyces cerevisiae (beticus, cheresiensis, montuliensis, rouxii) according to their abilities to ferment different sugars. It has been proposed that race succession during biological ageing is essential for the development of the organoleptical properties of sherry wines. In this work we studied the physiological characteristics, the molecular differentiation and the phylogenetic relationships of the four races employing type and reference strains from culture collections and natural environments. Using restriction analysis of the ribosomal region that includes th…
Distinct Clones of Yersinia pestis Caused the Black Death
2010
From AD 1347 to AD 1353, the Black Death killed tens of millions of people in Europe, leaving misery and devastation in its wake, with successive epidemics ravaging the continent until the 18th century. The etiology of this disease has remained highly controversial, ranging from claims based on genetics and the historical descriptions of symptoms that it was caused by Yersinia pestis to conclusions that it must have been caused by other pathogens. It has also been disputed whether plague had the same etiology in northern and southern Europe. Here we identified DNA and protein signatures specific for Y. pestis in human skeletons from mass graves in northern, central and southern Europe that …
Chemical communication in termites: syn-4,6-Dimethylundecan-1-ol as 3 trail-following pheromone, syn-4,6-dimethylundecanal and 4 (5E)-2,6,10-trimethy…
2011
The trail-following pheromone and sex pheromones were investigated in the Indomalayan termite Hodotermopsis sjoestedti belonging to the new family Archotermopsidae. Gas chromatography coupled to mass spectrometry (GC-MS) after solid phase microextraction (SPME) of the sternal gland secretion of pseudergates and trail-following bioassays demonstrated that the trailfollowing pheromone of H. sjoestedti was syn-4,6-dimethylundecan-1-ol, a new chemical structure for termite pheromones. GC-MS after SPME of the sternal gland secretion of alates also allowed the identification of sex-specific compounds. In female alates, the major sex-specific compound was identified as (5E)-2,6,10-trimethylundeca-…
Une chrysomèle contre l'ambroisie, est-ce réaliste ?
2016
Context - Despite intensive management practices carried out by stakeholders, common ragweed control is presently not sufficient to limit the spread of this annual invasive plant. Ali classical methods (mowing, chemical weeding, etc.) are limited in terms of efficiency. ln order to achieve a better management in the different habitats occupied by the plant, it is necessary to design innovative methods that could increase contra efficiency. The recent accidental introduction of a ragweed natural enemy in ltalia raises the question of the use of biological control agents. Could the regulation by a new phytophagous insect be considered as an integrated way of management in order to reduce the …
Permineralized coniferophytes from the Autun Basin: specimens from two new localities of Renault zone 3
2015
International audience; Four zones yielding silicified plant remains have been recognized in the Autun Basin by Renault (1893-1896). Zones 2, 3 and 4, characterized by Autunian plants, correspond to the successive formations of Igornay and Muse (lower Autunian), and Surmoulin-Millery (upper Autunian). Their paleobotanical content, together with that preserved as adpressions in the same formations, document paleofloral changes on the western side of the Tethys within a time interval extending from the latest Ghzelian (uppermost Pennsylvanian) to the early Sakmarian (lower Permian) (Broutin et al. 1999). The analyses realized so far indicate a progressive replacement of wetland plants by taxa…
La lutte biologique contre l'ambroisie à feuille d'armoise illustrée par l'exemple d'Ophraella communa : quels intérêts et quelles limites
2016
Common ragweed (Ambrosia artemisiifolia) was introduced in France over 150 years ago and its spreading across France now seems inexorable. The specific biology of this summer annual creates new problems for the managers of the various habitats where the plant can be found. The reduced possibility, or even the impossibility, to use traditional control means in certain environment conditions brings managers to consider biological control as one of the few possible means for slowing down the spread, or even pushing back the distribution area, of this invasive and allergenic plant. With Ophraella communa as an example, a reflection is presented on the benefit-risk balance of the introduction of…