Purification and preliminary characterization of a xylanase from Thermomyces lanuginosus strain SS-8

Thermomyces lanuginosus SS-8 was isolated from soil samples that had been collected from near self-heating plant material and its extracellular cellulase-free xylanase purified approximately 160-fold using ion exchange chromatography and continuous elution electrophoresis. This xylanase was thermoactive (optimum temperature 60 °C) at pH 6.0 and had a molecular weight of 23.79 kDa as indicated by SDS-PAGE electrophoresis. The xylanase rapidly hydrolyzed xylan directly to xylose without the production of intermediary xylo-oligosaccharides within 15 min of incubation under optimum conditions. This trait of rapidly degrading xylan to xylose as a sole end-product could have biotechnological potential in degradation of agro-wastes for bioethanol manufacturing industry

Differential contributions of peripheral and central mechanisms to pain in a rodent model of osteoarthritis

The mechanisms underlying the transition from acute nociceptive pain to centrally maintained chronic pain are not clear. We have studied the contributions of the peripheral and central nervous systems during the development of osteoarthritis (OA) pain. Male Sprague-Dawley rats received unilateral intra-articular injections of monosodium iodoacetate (MIA 1mg) or saline, and weight bearing (WB) asymmetry and distal allodynia measured. Subgroups of rats received intra-articular injections of, QX-314 (membrane impermeable local anaesthetic)+capsaicin, QX-314, capsaicin or vehicle on days 7, 14 or 28 post-MIA and WB and PWT remeasured. On days 7&14 post-MIA, but not day 28, QX-314+capsaicin signfcantly attenuated changes in WB induced by MIA, illustrating a crucial role for TRPV1 expressing nociceptors in early OA pain. The role of top-down control of spinal excitability was investigated. The mu-opioid receptor agonist DAMGO was microinjected into the rostroventral medulla, to activate endogenous pain modulatory systems, in MIA and control rats and refex excitability measured using electromyography. DAMGO (3ng) had a signifcantly larger inhibitory effect in MIA treated rats than in controls. These data show distinct temporal contribtuions of TRPV1 expressing nociceptors and opioidergic pain control systems at later timepoints

Sequential Delivery of Host-Induced Virulence Effectors by Appressoria and Intracellular Hyphae of the Phytopathogen Colletotrichum higginsianum

Phytopathogens secrete effector proteins to manipulate their hosts for effective colonization. Hemibiotrophic fungi must maintain host viability during initial biotrophic growth and elicit host death for subsequent necrotrophic growth. To identify effectors mediating these opposing processes, we deeply sequenced the transcriptome of Colletotrichum higginsianum infecting Arabidopsis. Most effector genes are host-induced and expressed in consecutive waves associated with pathogenic transitions, indicating distinct effector suites are deployed at each stage. Using fluorescent protein tagging and transmission electron microscopy-immunogold labelling, we found effectors localised to stage-specific compartments at the host-pathogen interface. In particular, we show effectors are focally secreted from appressorial penetration pores before host invasion, revealing new levels of functional complexity for this fungal organ. Furthermore, we demonstrate that antagonistic effectors either induce or suppress plant cell death. Based on these results we conclude that hemibiotrophy in Colletotrichum is orchestrated through the coordinated expression of antagonistic effectors supporting either cell viability or cell death

Fallstudie Sylt. Teilvorhaben: Soziale Repraesentationen von Entwicklungen in Natur- und Anthroposphaere auf Sylt vor dem Hintergrund globalen Wandels Schlussbericht

At the example of the potential dangers of future changes in the climate threatening the island of Sylt, the authors deal with the question of how global changes in the environment, their causes and effects and possible measures taken by local groups to prevent them can be perceived and assessed in the context of general developments. To do this, 70 key persons of the ''Sylt social system'' who had been selected systematically were questioned at two different times in semi-structured, open interviews. The minutes of the interviews were categorized and evaluated quantitatively, analysing their contents. The goal was to find out the social representations of possible changes in the climate and to prove that these mental models are group-specific. It was found that to the persons questioned, tourism industry and construction activities on the island were far more important subjects than changes in the climate or the subject of protecting the shores. Climate changes were referred to with relation to their effects which were seen in connection with natural events. As far as causes were concerned, traffic turned out to be very important to the persons questioned. As for the measures, preventing changes in the climate was found to be more important than adapting to its consequences. Differences in the social representation of the groups mainly corresponded with the subjects focussed on and the interests of each group. As a supplement to the interview study, 54 tourists were interviewed regarding various aspects of the main study with a standardized questionnaire.Am Beispiel der moeglichen Bedrohung Sylts durch zukuenftige Klimaaenderungen wird untersucht, wie globale Umweltveraenderungen, deren Ursachen und Auswirkungen sowie moegliche Gegenmassnahmen von lokalen Akteursgruppen im Kontext allgemeiner Entwicklungen wahrgenommen und bewertet werden. Dazu wurden 70 systematisch ausgewaehlte Schluesselpersonen des 'sozialen Systems Sylt' zu zwei Untersuchungszeitpunkten in halbstrukturierten, offenen Interviews befragt. Die Interviewprotokolle wurden kategorisiert und quantitativ inhaltsanalytisch ausgewertet. Ziel war die mehrfach kontextualisierte Erhebung der sozialen Repraesentationen moeglicher Klimaaenderungen sowie der Nachweis von Gruppenspezifitaet fuer diese mentalen Modelle. Wesentlich mehr als Klimaaenderungen oder auch die Kuestenschutzthematik erwiesen sich der Fremdenverkehr und die Bautaetigkeit auf der Insel als fuer die Befragten bedeutsame Themen. Klimaaenderungen selbst wurden vor allem von ihren Auswirkungen her thematisiert, die eher im Bereich der Natursphaere gesehen wurden. Auf der Ursachenseite spielte fuer die Probanden der Verkehr eine grosse Rolle. Bei den Massnahmen rangierte die Verhinderung des Klimawandels vor der Anpassung an seine Folgen. Unterschiede in den sozialen Repraesentationen der Akteursgruppen entsprachen im Wesentlichen den inhaltlichen Schwerpunkten bzw. Interessen der Gruppen. Ergaenzend zu der Interviewstudie wurden 54 Touristen mittels eines standardisierten Fragebogens zu verschiedenen Aspekten der Hauptuntersuchung befragt. (orig.)SIGLEAvailable from TIB Hannover: F01B1786 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung und Forschung, Berlin (Germany)DEGerman