Alexandra Schmidt results 44
· Newest (Page 1/2, per page 25)
Author: Alexandra Schmidt ×Clear All Filters
Search Results
The existence of thresholds for carcinogenic compounds is an important topic in toxicology and regulatory science. Traditionally, genotoxic carcinogens are thought to exhibit no thresholds. However, cellular defense mechanisms like DNA repair and apoptosis can neutralize low levels of genotoxic stress implying different Points of Departure (PoDs) for different cellular endpoints. Moreover, since cellular PoDs are regulated by...
Earth's biodiversity is central to ecosystem health and resilience, providing essential functions and services. The Red Sea is a recognised marine biodiversity hotspot with high endemism and unique environmental conditions that support extensive but poorly resolved biodiversity. Here, we applied metagenomic analyses to sediment samples collected from coastal to deep‐sea environments during the Red Sea Decade Expedition 2022 to...
To advance understanding of meiofauna, key components of marine benthic ecosystems, an international team conducted a morphology-based taxonomic survey and workshop around São Miguel, the largest Azorean island, in 2019. The survey yielded critical baseline data on meiofaunal diversity and, despite taxonomic challenges that limited identification of certain taxa, laid a solid foundation for further research. To expand these fi...
Multi‐Millennial Genetic Resilience of Baltic Diatom Populations Disturbed in the Past CenturiesNARA Subscribed
Little is known about the genetic diversity and stability of natural populations over millennial time scales, although the current biodiversity crisis calls for heightened understanding. Marine phytoplankton, the primary producers forming the basis of food webs in the oceans, play a pivotal role in maintaining marine ecosystems health and serve as indicators of environmental change. This study examines the genetic diversity an...
Within a citizen science project, 112 freshwater habitats in Austria were sampled to get bacterial cultures belonging to the genus Aquirufa using a strategy for targeted isolation. We focused on these bacteria because they are widespread and represent typical freshwater bacteria and, furthermore, the typic red pigmentation facilitates preselection. Among the 113 obtained Aquirufa strains were HETE-83D T , KTFRIE-69F T , OSTEIC...
Strains LEOWEIH-7C T and LEPPI-3A were isolated from the Leopoldskroner Weiher, a lake located in the city of Salzburg, Austria. 16S rRNA gene similarities and phylogenetic reconstructions with 16S rRNA gene sequences as well as based on genome sequences revealed that the new strains belong to the A. antheringensis branch of the genus Aquirufa . Calculated whole-genome average nucleotide identity (gANI) and digital DNA–DNA hyb...
Metatranscriptomics reveals contrasting effects of elevation on the activity of bacteria and bacterial viruses in soilNARA Subscribed
Soil microbial diversity affects ecosystem functioning and global biogeochemical cycles. Soil bacterial communities catalyse a diversity of biogeochemical reactions and have thus sparked considerable scientific interest. One driver of bacterial community dynamics in natural ecosystems has so far been largely neglected: the predator–prey interactions between bacterial viruses (bacteriophages) and bacteria. To generate ground le...
EditorialNARA Subscribed
Aquirufa lenticrescens sp. nov. and Aquirufa aurantiipilula sp. nov.: two new species of a lineage of widespread freshwater bacteriaNARA Subscribed
Two bacterial strains, 9H-EGSE T and 15D-MOB T , were isolated from small freshwater habitats located near Salzburg, Austria. They showed the highest 16S rRNA sequence similarities of 100% and 99.9%, respectively, with type strains of species of the genus Aquirufa ( Bacteroidota ). Genome-based phylogenetic reconstructions with 119 amino acid sequences assigned the new taxa to the two distinct branches of the genus Aquirufa ....
Formation of B- and M-group aflatoxins and precursors by Aspergillus flavus on maize and its implication for food safetyNARA Subscribed
Aflatoxins count to the most toxic known mycotoxins and are a threat to food safety especially in regions with a warm and humid climate. Contaminated food reaches consumers globally due to international trade, leading to stringent regulatory limits of aflatoxins in food. While the formation of aflatoxin (AF) B 1 by the filamentous fungus Aspergillus flavus is well investigated, less is known about the formation kinetics of its...
Non-aflatoxigenic Aspergillus flavus strains are used as a biocontrol system on maize fields to decrease the aflatoxin biosynthesis of aflatoxigenic A. flavus strains. A. flavus strain AF36 was the first commercially available biocontrol strain and is authorized for use on maize fields by the US Environmental Protection Agency, e.g., in Texas and Arizona. A droplet digital PCR (ddPCR) assay was developed to analyze the mechani...