Bodenmikrobiologie im Hochgebirge - zentrale Einflussfaktoren vor dem Hintergrund des Climate Change

Die Bodenmikrobiologie bekommt vor dem Hintergrund des climate change eine zusätzliche Bedeutung, da Mikroorganismen anders als alle andere Lebewesen nicht nur von gesteigerten Temperaturen beeinflusst werden, sondern auch aktiv – u.z. positiv wie negativ – in das Klimageschehen eingreifen können. Böden im Hochgebirge sind diesbezüglich und per se noch viel zu wenig erforscht und können darüber hinaus vor dem Hintergrund des Klimawandels als sehr gute Modelle für boreale und polare Regionen dienen, da Änderungen, die mit einer steigenden Seehöhe von 100 m im Gebirge einhergehen und somit den Änderungen in einem S-N-Transekt von ca. 400 km entsprechen, für riesige Gebiete relevant sind. Im internationalen GLORIA-Projekte werden weltweit 116 Standorte in 6 Kontinenten hinsichtlich der Auswirkungen des globalen Klimawandels auf vegetationskundliche Parameter untersucht. Im Rahmen des vorliegenden Projektes konnte erstmals einer der untersuchten master-sites des GLORIA-Forschungsprogramms, der Schrankogel mineralogisch, bodenchemisch und mikrobiologisch umfassend untersucht und die erhaltenen Daten mit abiotischen Standortfaktoren (Temperatur etc.) sowie botanischen Daten in Zusammenhang gebracht werden. Der Schrankogel befindet sich in den Ötztaler Alpen (Tirol/Österreich), ist 3.497 m hoch, verfügt über eine hinsichtlich der Steigung und der Geologie sehr konstante, fast über 1000 Höhenmeter reichende SW-Flanke und war somit für die geplanten Untersuchungen bestens geeignet. Anders als viele vergleichbare Studien, konnten sehr deutliche Beeinflussungen von mineralogischen, bodenchemischen und bodenmikrobiologischen Parametern nachgewiesen werden. Einige der erhobenen Parameter zeigten keinen linearen Zusammenhang mit zentralen Einflussfaktoren wie der Temperatur sondern einen sigmoiden Verlauf, wobei die stärksten Änderungen im mittleren, sogenannten alpin-nivalen Ökoton, in einer Höhe von ca. 3.000 m erfolgten. Der alpin-nivale Ökoton zeigte auch (festgestellt über den Nivalitätsindex) eine zentrale Grenze in der Vegetationsgesellschaft an, die mit Veränderungen der mikrobiellen Communities und Aktivitäten einherging. Dies betraf nicht nur Gesamtzahlen von Bacteria sondern auch die Abundanz methanogener Archaea, die für den Methankreislauf und damit den Klimawandel hochrelevant sind und bis zu einer Höhe von 3.497 m nachgewiesen werden konnten

Comparison of DNA extraction methods on different sample matrices within the same terrestrial ecosystem

Metataxonomic studies of ecosystem microbiotas require the simultaneous processing of samples with contrasting physical and biochemical traits. However, there are no published studies of comparisons of different DNA extraction kits to characterize the microbiotas of the main components of terrestrial ecosystems. Here, and to our knowledge for the first time, five DNA extraction kits were used to investigate the composition and diversity of the microbiota of a subset of samples typically studied in terrestrial ecosystems such as bulk soil, rhizosphere soil, invertebrate taxa and mammalian feces. DNA extraction kit was associated with changes in the relative abundance of hundreds of ASVs, in the same samples, resulting in significant differences in alpha and beta diversity estimates of their microbiotas. Importantly, the impact of DNA extraction kit on sample diversity varies according to sample type, with mammalian feces and soil samples showing the most and least consistent diversity estimates across DNA extraction kits, respectively. We show that the MACHEREY-NAGEL NucleoSpin® Soil kit was associated with the highest alpha diversity estimates, providing the highest contribution to the overall sample diversity, as indicated by comparisons with computationally assembled reference communities, and is recommended to be used for any large-scale microbiota study of terrestrial ecosystem

Fermented wheat germ extract - nutritional supplement or anticancer drug?

<p>Abstract</p> <p>Background</p> <p>Fermented wheat germ extract (FWGE) is a multisubstance composition and, besides others, contains 2-methoxy benzoquinone and 2, 6-dimethoxy benzoquinone which are likely to exert some of its biological effects. FWGE interferes with anaerobic glycolysis, pentose cycle and ribonucleotide reductase. It has significant antiproliferative effects and kills tumor cells by the induction of apoptosis via the caspase-poly [ADP-ribose] polymerase-pathway. FWGE interacts synergistically with a variety of different anticancer drugs and exerted antimetastatic properties in mouse models. In addition, FWGE modulates immune response by downregulation of MHC-I complex and the induction of TNF-α and various interleukins. Data in the F-344 rat model provide evidence for a colon cancer preventing effect of FWGE.</p> <p>Clinical data from a randomized phase II trial in melanoma patients indicate a significant benefit for patients treated with dacarbazine in combination with FWGE in terms of progression free survival (PFS) and overall survival (OS). Similarly, data from studies in colorectal cancer suggested a benefit of FWGE treatment. Besides extension of OS and PFS, FWGE improved the quality of life in several studies.</p> <p>Conclusion</p> <p>In conclusion, available data so far, justify the use of FWGE as a non-prescription medical nutriment for cancer patients. Further randomized, controlled and large scale clinical studies are mandatory, to further clarify the value of FWGE as a drug component of future chemotherapy regimens.</p

Demographic, clinical and antibody characteristics of patients with digital ulcers in systemic sclerosis: data from the DUO Registry

OBJECTIVES: The Digital Ulcers Outcome (DUO) Registry was designed to describe the clinical and antibody characteristics, disease course and outcomes of patients with digital ulcers associated with systemic sclerosis (SSc). METHODS: The DUO Registry is a European, prospective, multicentre, observational, registry of SSc patients with ongoing digital ulcer disease, irrespective of treatment regimen. Data collected included demographics, SSc duration, SSc subset, internal organ manifestations, autoantibodies, previous and ongoing interventions and complications related to digital ulcers. RESULTS: Up to 19 November 2010 a total of 2439 patients had enrolled into the registry. Most were classified as either limited cutaneous SSc (lcSSc; 52.2%) or diffuse cutaneous SSc (dcSSc; 36.9%). Digital ulcers developed earlier in patients with dcSSc compared with lcSSc. Almost all patients (95.7%) tested positive for antinuclear antibodies, 45.2% for anti-scleroderma-70 and 43.6% for anticentromere antibodies (ACA). The first digital ulcer in the anti-scleroderma-70-positive patient cohort occurred approximately 5 years earlier than the ACA-positive patient group. CONCLUSIONS: This study provides data from a large cohort of SSc patients with a history of digital ulcers. The early occurrence and high frequency of digital ulcer complications are especially seen in patients with dcSSc and/or anti-scleroderma-70 antibodies

Bacterial Communities Involved in Soil Formation and PlantEstablishment Triggered by Pyrite Bioweathering on ArcticMoraines

Abstract In arctic glacier moraines, bioweathering primed by microbial iron oxidizers creates fertility gradients that accelerate soil development and plant establishment. With the aim of investigating the change of bacterial diversity in a pyrite-weathered gradient, we analyzed the composition of the bacterial communities involved in the process by sequencing 16S rRNA gene libraries from different biological soil crusts (BSC). Bacterial communities in three BSC of different morphology, located within 1 m distance downstream a pyritic conglomerate rock, were significantly diverse. The glacier moraine surrounding the weathered site showed wide phylogenetic diversity and high evenness with 15 represented bacterial classes, dominated by Alphaproteobacteria and pioneer Cyanobacteria colonizers. The bioweathered area showed the lowest diversity indexes and only nine bacterial families, largely dominated by Acidobacteriaceae and Acetobacteraceae typical of acidic environments, in accordance with the low pH of the BSC. In the weathered BSC, iron-oxidizing bacteria were cultivated, with counts decreasing along with the increase of distance from the rock, and nutrient release from the rock was revealed by environmental scanning electron microscopy-energy dispersive X-ray analyses. The vegetated area showed the presence of Actinomycetales, Verrucomicrobiales, Gemmatimonadales, Burkholderiales, and Rhizobiales, denoting a bacterial community typical of developed soils and indicating that the lithoid substrate of the bare moraine was here subjected to an accelerated colonization, driven by iron-oxidizing activity