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Microarrays for the detection of toxic algae (MIDTAL)

Das Projekt "Microarrays for the detection of toxic algae (MIDTAL)" wird vom Umweltbundesamt gefördert und von Natural Environment Research Council, Marine Biological Association of the United Kingdom durchgeführt. Objective: Microalgae in marine and brackish waters of Europe regularly cause 'harmful effects', considered from the human perspective, in that they threaten public health and cause economic damage to fisheries and tourism. Cyanobacteria cause similar problems in freshwaters. These episodes encompass a broad range of phenomena collectively referred to as 'harmful algal blooms' (HABs). They include discoloration of waters by mass occurrences of microalgae (true algal blooms that may or may not be 'harmful') to toxin-producing species that may be harmful even in low cell concentrations. A broad classification of HAB distinguishes three groups of toxic organisms. For adequate management of these phenomena, monitoring of microalgae is required. However, the effectiveness of monitoring programmes is limited by the fact that it is time consuming and morphology as determined by light microscopy may be insufficient to give definitive species and toxin attribution. Once cell numbers reach a threshold level, then shellfish are selected to toxin analysis by the mouse bioassay. The mouse bioassay is continued on a daily basis until no more toxin is detected. Molecular and biochemical methods are now available that offer rapid means of both species and toxin detection. In this project we will target rapid species identification using rRNA genes as the target. We include antibodies to specific toxins because even when cell numbers are very low, the toxins can be present and can be accumulated in the shellfish. Microarrays are the state of the art technology in molecular biology for the processing of bulk samples for detection of target RNA/DNA sequences.. The purpose of MIDTAL is to support the common fisheries policy to aid the national monitoring agencies by providing new rapid tools for the identification of toxic algae and their toxins so that they can comply with ECC directive 91/1491/CEE that can be converted to cell numbers and reduce the need for the mouse bioassay.

Beobachtung der Zusammensetzung von Mikrobenpopulationen und ihrer natuerlichen und induzierten Veraenderung durch Trennung und Darstellung ribosomaler Nukleinsaeuresequenzen

Das Projekt "Beobachtung der Zusammensetzung von Mikrobenpopulationen und ihrer natuerlichen und induzierten Veraenderung durch Trennung und Darstellung ribosomaler Nukleinsaeuresequenzen" wird vom Umweltbundesamt gefördert und von Biologische Bundesanstalt für Land- und Forstwirtschaft durchgeführt. Die Heterogenitaet amplifizierter Zielsequenzen ribosomaler (16S-) DNA und RNA aus landwirtschaftlich genutzten Boeden und der Rhizosphaere von Nutzpflanzen wird durch Trennung in einer Temperaturgradienten-Gelelektrophorese (TGGE) dargestellt. Die erhaltenen Verteilungsmuster werden eingesetzt, um die Veraenderung oder Bewahrung der Vielfalt der mikrobiellen Gemeinschaften bei induzierten Eingriffen im Vergleich mit natuerlichen Variabilitaeten zu pruefen und evtl. neue Bewertungsmassstaebe fuer die Bewertung solcher Eingriffe einschliesslich des Einsatzes gentechnisch veraenderter Organismen zu erhalten.

Evolution von Foraminiferen, molekularer gegenueber mikropalaeontologischem Ansatz

Das Projekt "Evolution von Foraminiferen, molekularer gegenueber mikropalaeontologischem Ansatz" wird vom Umweltbundesamt gefördert und von Universite de Geneve, Departement de Zoologie et Biologie Animale durchgeführt. Foraminifera are marine protozoa, which tests deposited in the sediments since the Early Cambrian are the most widely used microfossils in biostratigraphy and paleoenvironmental reconstructions. Paleontology provides abundant information concerning the fossil record of foraminifera, however, their origin and the macro-evolutionary relationsships between the major groups are not well established. The aim of this project is to compare the micropaleontological data on evolution of foraminifera to their phylogeny inferred from the ribosomal RNA gene sequences. Analysis of the SSU and LSU rDNA sequences allowed to establish the phylogenetic position of foraminifera and proposed a new model of phylogenetic relationsships within this group. This project has been developed in context of recent advancements in application of molecular techniques to the study of systematics based on analysis of nucleic acids sequences has opened the new avenues for development of our knowledge of origin and evolutionary history of living organisms.^Les Foraminiferes sont un groupe de Protistes dont les tests, deposes dans les sediments marins depuis des millions d'annees, sont largement utilises en geologie pour leur qualite de marqueurs dans l'analyse biostratigraphique ainsi que dans les reconstructions paleoecologiques et paleographiques. De nombreuses lignees phylogenetiques de Foraminiferes ont ete etudiees, cependant leur macroevolution, a savoir les relations entre les principaux groupes taxonomiques, reste largement inconnue. Nos recherches ont pour but d'etudier la macroevolution des Foraminiferes a l'aide des sequences des ARN ribosomiques. L'analyse comparee de sequences de la grande et de la petite sous-unite de l'ARN ribosomique a permis d'etablir la relation phylogenetique des Foraminiferes avec d'autres eucaryotes unicellulaires et de construire une phylogenie du groupe. Ce projet se situe dans le contexte de l'application de techniques modernes de la biologie moleculaire au renouvellement de la systematique animale et vegetale. Basee sur l'analyse comparative de sequences d'acides nucleiques, la systematique moleculaire a ouvert de nouvelles perspectives dans l'interpretation des origines et de l'historie evolutive des etres vivants. (FRA)

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