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Burgstaller, S.

Publications and source records attributed to Burgstaller, S..

3 recordsLinked to original sources

Land-use preferences of the European green toad (Bufotes viridis) in the city of Vienna (Austria): the importance of open land in urban environments

Urban areas are increasing worldwide, which poses treats to animal wildlife. However, in certain cases cities can provide refuges for endangered animals. The European green toad (Bufotes viridis) is one of such examples, which is known from cities throughout their distribution. In contrast, considerable areas of their former (primary) habitats have been degraded. The primary habitats of this species include steppes and wild river floodplains, both characterized by dynamic changes and the presence of open areas. We used available green toad observation data (2007-2020) to model the effects of land-use types on occurrence probability in the city of Vienna. Forest and densely populated areas were highly significantly negatively associated with green toad presence, while transformation/construction site areas showed a strong positive effect. Such occurrence pattern might be characteristic for early succession species, which depend on stochastic environmental disturbances (e.g., droughts and floods) in their primary habitats. We argue that urban landscape planning should appreciate the potential ecological value of open land in cities which is either in a transition phase or a permanent wasteland. Ecological managing of such landscape could vastly increase urban biodiversity.

ecology↗

Monitoring extracellular ion and metabolite dynamics with recombinant nanobody-fused biosensors

The tumor microenvironment (TME) consists of different cell types that secrete proteins and also control the extracellular concentration of ions and metabolites. Changes in these intra-tumoral analytes and conditions, including K+, glucose, and pH, have been described to alter the metabolic activity of cancer cells, promote tumor cell growth, and impair anti-tumor immunity. However, the mechanisms regulating ion and metabolite levels and their effects on certain characteristics of the TME are still poorly understood. Therefore, accurate determination and visualization of analyte or state changes in real time within the TME is desired. In this study, we genetically combined FRET-based fluorescent biosensors with nanobodies (Nbs) and used them for targeted visualization and monitoring of extracellular changes in K+, pH, and glucose on cell surfaces. We demonstrated that these recombinant biosensors quantitatively visualize extracellular K+ alterations on multiple cancer and non-cancer cell lines and primary neurons. By implementing a HER2 specific Nb, we generated K+ and pH sensors, which retain their functionality and specifically stained HER2 positive breast cancer cells. Based on the successful technical development of several Nb-biosensor combinations, we anticipate that this approach can be easily extended to design other targeted biosensors. Such versatile probes will open new possibilities for the reliable study of extracellular analytes in advanced 3D cell models or even in vivo systems.

biochemistry↗

A Large-scale Drug Repositioning Survey for SARS-CoV-2 Antivirals

The emergence of novel SARS coronavirus 2 (SARS-CoV-2) in 2019 has triggered an ongoing global pandemic of severe pneumonia-like disease designated as coronavirus disease 2019 (COVID-19). To date, more than 2.1 million confirmed cases and 139,500 deaths have been reported worldwide, and there are currently no medical countermeasures available to prevent or treat the disease. As the development of a vaccine could require at least 12-18 months, and the typical timeline from hit finding to drug registration of an antiviral is >10 years, repositioning of known drugs can significantly accelerate the development and deployment of therapies for COVID-19. To identify therapeutics that can be repurposed as SARS-CoV-2 antivirals, we profiled a library of known drugs encompassing approximately 12,000 clinical-stage or FDA-approved small molecules. Here, we report the identification of 30 known drugs that inhibit viral replication. Of these, six were characterized for cellular dose-activity relationships, and showed effective concentrations likely to be commensurate with therapeutic doses in patients. These include the PIKfyve kinase inhibitor Apilimod, cysteine protease inhibitors MDL-28170, Z LVG CHN2, VBY-825, and ONO 5334, and the CCR1 antagonist MLN-3897. Since many of these molecules have advanced into the clinic, the known pharmacological and human safety profiles of these compounds will accelerate their preclinical and clinical evaluation for COVID-19 treatment.

microbiology↗