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Biology subjects

Kaster, A.-K.

Publications and source records attributed to Kaster, A.-K..

2 recordsLinked to original sources

Midi-metagenomics: A novel approach for cultivation independent microbial genome reconstruction from environmental samples

Since the majority of microbial organisms still evade cultivation attempts, genomic insights into many taxa are limited to cultivation-independent approaches. However, current methods of metagenomics and single cell genome sequencing have individual drawbacks, which can limit the quality as well as completeness of the reconstructed genomes. Current attempts to combine both approaches still use amplification techniques which are prone to bias. Here, we propose a novel approach for the purpose of genome reconstructions, that utilizes the potential of cell sorting for targeted enrichment and depletion of different cell types to create distinct cell fractions of sufficient size, circumventing amplification. By distributing sequencing efforts over these fractions as well as the original sample, co-assemblies become highly optimized for co-abundance variation based binning approaches. "Midi-metagenomics" enables accurate metagenome assembled genome (MAG) reconstruction from individual sorted samples with higher quality than co-assembly of multiple distinct samples and has potential for the targeted enrichment and sequencing of microbial dark matter.

genomics↗

A genetically-encoded three-colour stress biosensor reveals multimodal response at single cell level and spatiotemporal dynamics of biofilms

The plethora of chemical, physical, and biological factors that can damage microbial cells has triggered the evolution of sophisticated stress response (SR) mechanisms. While individual SR pathways have been monitored with genetically encoded reporters, sensor concepts for the detection of multimodal effects of stressing conditions in living microorganisms are still lacking. Orthogonally detectable red, green, and blue fluorescent proteins combined in a single vector system, dubbed RGB-S reporter, enable the simultaneous, independent and real-time analysis of the stress response in Escherichia coli to physiological stress, genotoxicity, and cytotoxicity. The sensor system can be read out via conventional fluorescence microscopy or microtiter plate analysis and can also be combined with Fluorescent Activated Cell Sorting (FACS) and subsequent transcriptome analysis. Various stressors, such as the biotechnologically relevant 2-propanol, lead to the activation of one, two or all three SRs, which can have a significant impact on non-stress-related metabolic pathways. Implemented in microfluidic cultivation with confocal fluorescence microscopy imaging, the technology enabled spatiotemporal analysis of live biofilms to discover stratified subpopulations of bacteria with heterogeneous stress responses.

microbiology↗