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Geo-climatic changes and apomixis as major drivers of diversification in the Mediterranean sea lavenders (Limonium Mill.) (2021)

Konstantina Koutroumpa Ben H. Warren Spyros Theodoridis Mario Coiro Maria M. Romeiras Ares Jiménez Elena Conti

The Mediterranean realm, comprising the Mediterranean and Macaronesian regions, has long been recognized as one of the world’s biodiversity hotspots, owing to its remarkable species richness and endemism. Several hypotheses on biotic and abiotic drivers of species diversification in the region have been often proposed but rarely tested in an explicit phylogenetic framework. Here, we investigate the impact of both species-intrinsic and -extrinsic factors on diversification in the species-rich, cosmopolitan Limonium, an angiosperm genus with center of diversity in the Mediterranean. First, we infer and time-calibrate the largest Limonium phylogeny to date. We then estimate ancestral ranges and diversification dynamics at both global and regional scales. At the global scale, we test whether the identified shifts in diversification rates are linked to specific geological and/or climatic events in the Mediterranean area and/or asexual reproduction (apomixis). Our results support a late Paleogene origin in the proto-Mediterranean area for Limonium, followed by extensive in situ diversification in the Mediterranean region during the late Miocene, Pliocene, and Pleistocene. We found significant increases of diversification rates in the “Mediterranean lineage” associated with the Messinian Salinity Crisis, onset of Mediterranean climate, Plio-Pleistocene sea-level fluctuations, and apomixis. Additionally, the Euro-Mediterranean area acted as the major source of species dispersals to the surrounding areas. At the regional scale, we infer the biogeographic origins of insular endemics in the oceanic archipelagos of Macaronesia, and test whether woodiness in the Canarian Nobiles clade is a derived trait linked to insular life and a biotic driver of diversification. We find that Limonium species diversity on the Canary Islands and Cape Verde archipelagos is the product of multiple colonization events followed by in situ diversification, and that woodiness of the Canarian endemics is indeed a derived trait but is not associated with a significant shift to higher diversification rates. Our study expands knowledge on how the interaction between abiotic and biotic drivers shape the uneven distribution of species diversity across taxonomic and geographical scales.

Energy conservation in the acetogenic bacterium clostridium aceticum (2021)

Anja Wiechmann Volker Müller

In times of global warming caused by the extensive use of fossil fuels, the need to capture gaseous carbon compounds is growing bigger. Several groups of microorganisms can fix the greenhouse gas CO2. Out of these, acetogenic bacteria are role models in their ability to reduce CO2 with hydrogen to acetate, which makes acetogens prime candidates for genetic modification towards biotechnological production of value-added compounds from CO2, such as biofuels. However, growth of acetogens on gaseous substrates is strongly energy-limited, and successful metabolic engineering requires a detailed knowledge of the bioenergetics. In 1939, Clostridium aceticum was the first acetogen to be described. A recent genomic study revealed that this organism contains cytochromes and therefore may use a proton gradient in its respiratory chain. We have followed up these studies and will present data that C. aceticum does not use a H+ but a Na+ gradient for ATP synthesis, established by a Na+-Rnf. Experimental data and in silico analyses enabled us to propose the biochemistry and bioenergetics of acetogenesis from H2 + CO2 in C. aceticum.

Lehre in Zeiten von Corona : die Didaktik der Biowissenschaften hat sich einiges einfallen lassen, um eine hohe Lehrqualität auch in Zeiten der Pandemie zu gewährleisten (2021)

Marilú Liliana Huertas de Schneider Volker Wenzel Anna Lena Burger Sandra Formella-Zimmermann

Beobachten, untersuchen, experimentieren: Wie soll das gehen unter Pandemiebedingungen? Wenn auch die Chancen der digitalen Medien nun gezwungenermaßen zusehends sichtbar wurden, so sind gerade für angehende Biologielehrkräfte Primärerfahrungen mit originalen Organismen und das Einüben naturwissenschaftlicher Arbeitsmethoden sehr wichtig...

Resolving recalcitrant clades in the pantropical ochnaceae: insights from comparative phylogenomics of plastome and nuclear genomic data derived from targeted sequencing (2021)

Julio Valentin Schneider Juraj Paule Tanja Jungcurt Domingos Cardoso André Márcio Amorim Thomas Berberich Georg Zizka

Plastid DNA sequence data have been traditionally widely used in plant phylogenetics because of the high copy number of plastids, their uniparental inheritance, and the blend of coding and non-coding regions with divergent substitution rates that allow the reconstruction of phylogenetic relationships at different taxonomic ranks. In the present study, we evaluate the utility of the plastome for the reconstruction of phylogenetic relationships in the pantropical plant family Ochnaceae (Malpighiales). We used the off-target sequence read fraction of a targeted sequencing study (targeting nuclear loci only) to recover more than 100 kb of the plastid genome from the majority of the more than 200 species of Ochnaceae and all but two genera using de novo and reference-based assembly strategies. Most of the recalcitrant nodes in the family’s backbone were resolved by our plastome-based phylogenetic inference, corroborating the most recent classification system of Ochnaceae and findings from a phylogenomic study based on nuclear loci. Nonetheless, the phylogenetic relationships within the major clades of tribe Ochnineae, which comprise about two thirds of the family’s species diversity, received mostly low support. Generally, the phylogenetic resolution was lowest at the infrageneric level. Overall there was little phylogenetic conflict compared to a recent analysis of nuclear loci. Effects of taxon sampling were invoked as the most likely reason for some of the few well-supported discords. Our study demonstrates the utility of the off-target fraction of a target enrichment study for assembling near-complete plastid genomes for a large proportion of samples.

Functional expression of the human glucose transporters GLUT2 and GLUT3 in yeast offers novel screening systems for GLUT-targeting drugs (2021)

Sina Schmidl Sebastian A. Tamayo Rojas Cristina V. Iancu Jun-Yong Choe Igor-Mislav Oreb

Human GLUT2 and GLUT3, members of the GLUT / SLC2 gene family, facilitate glucose transport in specific tissues. Their malfunction or misregulation is associated with serious diseases, including diabetes, metabolic syndrome, and cancer. Despite being promising drug targets, GLUTs have only a few specific inhibitors. To identify and characterize potential GLUT2 and GLUT3 ligands, we developed a whole-cell system based on a yeast strain deficient in hexose uptake, whose growth defect on glucose can be rescued by the functional expression of human transporters. The simplicity of handling yeast cells makes this platform convenient for screening potential GLUT2 and GLUT3 inhibitors in a growth-based manner, amenable to high-throughput approaches. Moreover, our expression system is less laborious for detailed kinetic characterization of inhibitors than alternative methods such as the preparation of proteoliposomes or uptake assays in Xenopus oocytes. We show that functional expression of GLUT2 in yeast requires the deletion of the extended extracellular loop connecting transmembrane domains TM1 and TM2, which appears to negatively affect the trafficking of the transporter in the heterologous expression system. Furthermore, single amino acid substitutions at specific positions of the transporter sequence appear to positively affect the functionality of both GLUT2 and GLUT3 in yeast. We show that these variants are sensitive to known inhibitors phloretin and quercetin, demonstrating the potential of our expression systems to significantly accelerate the discovery of compounds that modulate the hexose transport activity of GLUT2 and GLUT3.

Water security and rangeland sustainability: Transdisciplinary research insights from Namibian–German collaborations (2021)

Robert Lütkemeier Meed Mbidzo Stefan Liehr

The Global South is facing severe challenges in ensuring livelihood security due to climate change impacts, environmental degradation and population growth as well as changing lifestyles. These complex problems cannot be solely solved by single scientific disciplines – they require transdisciplinary research (TDR). Stakeholders from civil society, the corporate sector, government and science need to pool their knowledge to find solutions for sustainable transformations. In Namibia, we have been involved in TDR projects on water supply, and sanitation services as well as livestock management in rangeland systems. In this paper, we review two TDR projects that differ in multiple ways and hence allow us to carve out structural differences and critically discuss research outcomes, lessons learned and the challenge of North–South collaborations. Our review builds upon published and unpublished project documents as well as expert interviews with Namibian and German researchers who were involved in the projects. Our results show that TDR can be put into practice in different ways, depending on the research focus and the period available. The TDR phases of problem framing, inter- and transdisciplinary integration were implemented with different tools and foci points. We discuss the role of project length and funding conditions for project success and outcome generation. In addition, we critically consider the role of Namibian and German researchers in these international collaborations. The conclusions we draw touch upon the points of preparatory research funding, the equal acknowledgement of Global South contributions to joint research projects and the explicit handling of TDR components in project work. Significance: • The current social-ecological challenges are complex and require TDR as a mode of knowledge coproduction, particularly in a development context. • Inter- and transdisciplinary integration are critical processes for a project to be successful and require the allocation of adequate time and monetary resources. • Longer-term projects with a funded preparatory research phase constitute a structural model for TDR as project outcomes can evolve over time. • Global South researchers carry a hidden burden in international collaborations that has to be adequately acknowledged upfront in project planning and final products.

Analytical screening of organic chemicals of emerging concern in western Kenya and their contribution to the prevalence of schistosomiasis (2021)

Faith Jebiwot Kandie

In the past decades, the use and production of chemicals has been on the rise globally due to increasing industrialization and intensive agriculture; resulting in the occurrence and ecotoxicological risks of chemicals of emerging concern (CECs) in the aquatic compartments. Risks include changes in community structure resulting in the dominance of one species and ecosystem imbalance. When dominant disease-causing organisms are in the environment, the disease transmission is increased. For example, host snails for the schistosomiasis, a human trematode disease, are known to be tolerant to pesticide exposure compared to the predators. This would therefore result in an increased abundance of snails which consequently increase the disease transmission in the human population. Kenya, being a low income country faces a lot of challenges with provision of clean water, diseases and sanitation facilities, and increasing population which results in intensive agriculture coupled with pesticide use. Although a lot of research has been carried out on the environmental occurrence and risk of CECs (Chapter 1), most of these studies have been done in developed countries with limited information from Africa. Additionally, research in Africa focused on urban areas with limited number of compounds analyzed and mostly in the water phase, and inadequate information on the effects of CECs on the aquatic organisms. In order to reduce this knowledge gap, this dissertation focused on identification and quantification of CECs present in water, sediment and snails from western Kenya, and the contribution of pesticides to the transmission of schistosomiasis. Chapter 2 gives a summary of the results and discussion of the dissertation. In Chapter 3, a comprehensive chemical analysis was carried out on 48 water samples to identify compounds, spatial patterns and associated risks for fish, crustacean and algae using toxic unit (TU) approach. A total of 78 compounds were detected with pesticides and biocides being the compounds most frequently detected. Spatial pattern analysis revealed limited compound grouping based on land use. Acute risk for crustaceans and algae were driven by one to three individual compounds. These compounds responsible for toxicity were prioritized as candidate compounds for monitoring and regulation in Kenya. In Chapter 4, an extension of Chapter 3 was done to cover the CECs present in snails and sediment from the 48 sites. A total of 30 compounds were found in snails and 78 in sediments with 68 additional compounds being found which were not previously detected in water. Higher contaminant concentrations were found in agricultural sites than in areas without anthropogenic activities. The highest acute toxicity (TU 0.99) was determined for crustaceans based on compounds in sediment samples. The risk was driven by diazinon and pirimiphos-methyl. Acute and chronic risks to algae were driven by diuron whereas fish were found to be at low to no acute risk. In Chapter 5, the effect of pesticide contamination on schistosomiasis transmission was evaluated by applying complimentary laboratory and field studies. In the field studies, the ecological mechanisms through which pesticides and physical chemical parameters affect host snails, predators and competitors were investigated. Pesticide data was obtained from the results in chapter 3. The overall distribution of grazers and predators was not affected by pesticide pollution. However, within the grazers, pesticide pollution increased dominance of host snails. On the contrary, the host-snail competitors were highly sensitive to pesticide exposure. For the laboratory studies, macroinvertebrates including Schistosoma-host snails, competitors and predators were exposed to 6 concentrations levels of imidacloprid and diazinon. Snails showed higher insecticide tolerance compared to competitors and predators. Finally, Chapter 6 summarizes the conclusions of this dissertation, placing it in a broader context. In this dissertation, a comprehensive chemical characterization and risk assessment of CECs has been carried out in freshwater systems; together with the effects of pesticides on schistosomiasis transmission in rural western Kenya. Results of this dissertation showed that rural areas are contaminated posing a risk to aquatic organisms which contribute to schistosomiasis transmission. This shows the need for regular monitoring and policy formulation to reduce pollutant emissions which contributes negatively to both ecological and human health effects.

Exploring the construct of relational values: an empirical approach (2020)

Matthias Winfried Kleespies Paul Wilhelm Dierkes

In recent environmental research, relational values (RVs) have emerged as a new group of values to explain environmental behavior. Although this new concept is attracting attention, empirical studies on the subject are still rare. On this basis, we have conducted three studies to analyze an existing measurement tool for RVs and compared the construct with the concept of connection to nature. In study 1, we confirmed convergent and discriminant validity of the RV scale by comparing it with the Two Factor Model of Environmental Values (2-MEV) model using a sample of n = 350 university students. Additionally, study 1 verified reliability using test–retest reliability on three different groups of students (n1 = 53; n2 = 37; n3 = 48). In study 2, principal component analyses were performed to examine the structure of RVs and to compare it to the concept of connection to nature by reusing the sample 350 university students from study 1. The results show that RVs and connection to nature are not fundamentally distinct constructs, but overlap. However, if the structure of the RV measurement is forced to a single factor, no perfect fit is found, making a multidimensional solution more likely. A third study was conducted to review the results from study 2 using confirmatory factor analysis on a new sample of 878 university and high school students. Study 3 confirmed RVs as a multidimensional construct with three factors: care, community, and connection. It also proved the overlap of the connection to nature and RV concepts to some extent.

Ordnung des Fachbereichs Biowissenschaften der Johann Wolfgang Goethe-Universität Frankfurt am Main für den Masterstudiengang Molekulare Biotechnologie mit dem Abschluss "Master of Science (M. Sc.)" vom 08. Juni 2015, zuletzt geändert am 10. September 2018 : hier: Dritte Änderung vom 22. Juni 2020 ; genehmigt vom Präsidium in der Sitzung am 1. September 2020 (2020)

A complete digitization of german herbaria is possible, sensible and should be started now (2020)

Thomas Borsch Albert-Dieter Stevens Eva Häffner Anton Güntsch Walter G. Berendsohn Marc Sebastian Appelhans Christina Barilaro Bánk Beszteri Frank R. Blattner Oliver Bossdorf Helmut Dalitz Stefan Dressler Rhinaixa Duque-Thüs Hans-Joachim Esser Andreas Franzke Dethardt Goetze Michaela Grein Uta Grünert Frank Hellwig Jörn Hentschel Elvira Hörandl Thomas Janßen Norbert Jürgens Gudrun Kadereit Timm Karisch Marcus A. Koch Frank Müller Jochen Müller Dietrich Ober Stefan Porembski Peter Poschlod Christian Printzen Martin Röser Peter Sack Philipp Schlüter Marco Schmidt Martin Schnittler Markus Scholler Matthias Schultz Elke Seeber Josef Simmel Michael Stiller Mike Thiv Holger Thüs Natalia Tkach Dagmar Triebel Ursula Warnke Tanja Weibulat Karsten Wesche Andrey Yurkov Georg Zizka

Plants, fungi and algae are important components of global biodiversity and are fundamental to all ecosystems. They are the basis for human well-being, providing food, materials and medicines. Specimens of all three groups of organisms are accommodated in herbaria, where they are commonly referred to as botanical specimens.The large number of specimens in herbaria provides an ample, permanent and continuously improving knowledge base on these organisms and an indispensable source for the analysis of the distribution of species in space and time critical for current and future research relating to global biodiversity. In order to make full use of this resource, a research infrastructure has to be built that grants comprehensive and free access to the information in herbaria and botanical collections in general. This can be achieved through digitization of the botanical objects and associated data.The botanical research community can count on a long-standing tradition of collaboration among institutions and individuals. It agreed on data standards and standard services even before the advent of computerization and information networking, an example being the Index Herbariorum as a global registry of herbaria helping towards the unique identification of specimens cited in the literature.In the spirit of this collaborative history, 51 representatives from 30 institutions advocate to start the digitization of botanical collections with the overall wall-to-wall digitization of the flat objects stored in German herbaria. Germany has 70 herbaria holding almost 23 million specimens according to a national survey carried out in 2019. 87% of these specimens are not yet digitized. Experiences from other countries like France, the Netherlands, Finland, the US and Australia show that herbaria can be comprehensively and cost-efficiently digitized in a relatively short time due to established workflows and protocols for the high-throughput digitization of flat objects.Most of the herbaria are part of a university (34), fewer belong to municipal museums (10) or state museums (8), six herbaria belong to institutions also supported by federal funds such as Leibniz institutes, and four belong to non-governmental organizations. A common data infrastructure must therefore integrate different kinds of institutions.Making full use of the data gained by digitization requires the set-up of a digital infrastructure for storage, archiving, content indexing and networking as well as standardized access for the scientific use of digital objects. A standards-based portfolio of technical components has already been developed and successfully tested by the Biodiversity Informatics Community over the last two decades, comprising among others access protocols, collection databases, portals, tools for semantic enrichment and annotation, international networking, storage and archiving in accordance with international standards. This was achieved through the funding by national and international programs and initiatives, which also paved the road for the German contribution to the Global Biodiversity Information Facility (GBIF).Herbaria constitute a large part of the German botanical collections that also comprise living collections in botanical gardens and seed banks, DNA- and tissue samples, specimens preserved in fluids or on microscope slides and more. Once the herbaria are digitized, these resources can be integrated, adding to the value of the overall research infrastructure. The community has agreed on tasks that are shared between the herbaria, as the German GBIF model already successfully demonstrates.We have compiled nine scientific use cases of immediate societal relevance for an integrated infrastructure of botanical collections. They address accelerated biodiversity discovery and research, biomonitoring and conservation planning, biodiversity modelling, the generation of trait information, automated image recognition by artificial intelligence, automated pathogen detection, contextualization by interlinking objects, enabling provenance research, as well as education, outreach and citizen science.We propose to start this initiative now in order to valorize German botanical collections as a vital part of a worldwide biodiversity data pool.

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