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The increasing incidence of bloodstream infections including sepsis is a major challenge in intensive care units worldwide. However, current diagnostics for pathogen identification mainly depend on culture- and molecular-based approaches, which are not satisfactory regarding specificity, sensitivity, and time to diagnosis. Herein, we established a complete diagnostic workflow for real-time high-throughput sequencing of cell-free DNA from plasma based on nanopore sequencing for the detection of the causative agents, which was applied to the analyses of eight samples from four septic patients and three healthy controls, and subsequently validated against standard next-generation sequencing results. By optimization of library preparation protocols for short fragments with low input amounts, a 3.5-fold increase in sequencing throughput could be achieved. With tailored bioinformatics workflows, all eight septic patient samples were found to be positive for relevant pathogens. When considering time to diagnosis, pathogens were identified within minutes after start of sequencing. Moreover, an extrapolation of real-time sequencing performance on a cohort of 239 septic patient samples revealed that more than 90% of pathogen hits would have also been detected using the optimized MinION workflow. Reliable identification of pathogens based on circulating cell-free DNA sequencing using optimized workflows and real-time nanopore-based sequencing can be accomplished within 5 to 6 hours following blood draw. Therefore, this approach might provide therapy-relevant results in a clinically critical timeframe.

This study aimed to uncover microbial dynamics and transcriptional adaptations during mesophilic AD of maize silage and slurry. While one digester performed under optimal conditions, the investigations also evaluated the microbiome during a temperature drop mediated process failure accompanied by acidification and how it contributed to a process recovery. Composition and pathway activities were analyzed by whole genome shotgun (WGS) and metatranscriptome sequencing, respectively. A biodiversity of 112 species was observed with noticeable shifts over process time. Although four distinct groups of microbes could be identified with a correlating versatility according to substrate and to process disturbance, also tremendous effects on gene expression were monitored especially of the archaeal methane metabolism. Particularly, the expression of acetogenotrophic methanogenesis related genes was identified to be relevant for process regeneration.

Infectious diseases have long been regarded as losing their threat to mankind. However, in the recent decades infectious diseases have been regaining grounds and are back in the focus of research. This is also due to the fact that medical progress has enabled us to treat and cure a much higher fraction of severe diseases or trauma, resulting in a significant proportion of temporarily or constantly immune-suppressed patients. Infectious diseases result from the interplay between pathogenic microorganisms and the hosts they infect, especially their defense systems. Consequently, immune-suppressed patients are at high risk to succumb from opportunistic infections, like Candida infections. To study the balance between host and C. albicans with regard to the establishment of disease or asymptomatic, commensal colonisation, we developed host-pathogen interaction systems to study both the adaptation of C. albicans to different epithelia as well as to investigate the sensors of the innate immune system, the pattern recognition receptors. These host-pathogen interaction systems, as well as some of the results gained are described in this review.

Nucleo-cytoplasmic transport of proteins is mostly mediated by specific interaction between transport receptors of the importin beta family and signal sequences present in their cargo. While several signal sequences, in particular the classical nuclear localization signal (NLS) recognized by the heterodimeric importin alpha/beta complex are well known, the signals recognized by other importin beta-like transport receptors remain to be characterized in detail. Here we present the systematic analysis of the nuclear import of Saccharomyces cerevisiae Asr1p, a nonessential alcohol-responsive Ring/PHD finger protein that shuttles between nucleus and cytoplasm but accumulates in the nucleus upon alcohol stress. Nuclear import of Asr1p is constitutive and mediated by its C-terminal domain. A short sequence comprising residues 243-280 is sufficient and necessary for active targeting to the nucleus. Moreover, the nuclear import signal is conserved from yeast to mammals. In vitro, the nuclear localization signal of Asr1p directly interacts with the importins Kap114p, Kap95p, Pse1p, Kap123p, or Kap104p, interactions that are sensitive to the presence of RanGTP. In vivo, these importins cooperate in nuclear import. Interestingly, the same importins mediate nuclear transport of histone H2A. Based on mutational analysis and sequence comparison with a region mediating nuclear import of histone H2A, we identified a ;novel type of NLS with the consensus sequence R/KxxL(x)(n)V/YxxV/IxK/RxxxK/R that is recognized by five yeast importins and connects them into a highly efficient network for nuclear import of proteins.