Individual Physiological Adaptations Enable Selected Bacterial Taxa To Prevail during Long-Term Incubations

Enclosure experiments are frequently used to investigate the impact of changing environmental conditions on microbial assemblages. Yet, how the incuba- tion itself challenges complex bacterial communities is thus far unknown. In this study, metaproteomic profiling, 16S rRNA gene analyses, and cell counts were com- bined to evaluate bacterial communities derived from marine, mesohaline, and oli- gohaline conditions after long-term batch incubations. Early in the experiment, the three bacterial communities were highly diverse and differed significantly in their compositions. Manipulation of the enclosures with terrigenous dissolved organic car- bon resulted in notable differences compared to the control enclosures at this early phase of the experiment. However, after 55 days, bacterial communities in the ma- nipulated and the control enclosures under marine and mesohaline conditions were all dominated by gammaproteobacterium Spongiibacter. In the oligohaline enclo- sures, actinobacterial cluster I of the hgc group (hgc-I) remained abundant in the late phase of the incubation. Metaproteome analyses suggested that the ability to use outer membrane-based internal energy stores, in addition to the previously de- scribed grazing resistance, may enable the gammaproteobacterium Spongiibacter to prevail in long-time incubations. Under oligohaline conditions, the utilization of ex- ternal recalcitrant carbon appeared to be more important (hgc-I). Enclosure experi- ments with complex natural microbial communities are important tools to investi- gate the effects of manipulations. However, species-specific properties, such as individual carbon storage strategies, can cause manipulation-independent effects and need to be considered when interpreting results from enclosures.This study was financially supported by the SAW-funded ATKiM project, which provided funds to D. P. R. Herlemann, C. Meeske, K. Jürgens, S. Markert, and T. Schweder. D. P. R. Herlemann was also supported by the European Regional Develop- ment Fund/Estonian Research Council funded Mobilitas Plus Top Researcher grant MOBTT24. We thank the crew and captain of the RV Meteor (M86, M87) for support during the research cruise. The computations were performed on resources provided by the Swedish National Infrastructure for Computing (SNIC) at the PDC Centre for High Performance Computing (PDC-HPC) and Uppsala Multidisciplinary Center for Advanced Computational Science (UPPMAX). We thank Jana Matulla for excellent technical assis- tance and Stephan Fuchs for his help and advice in MS database construction. We also thank Stefan E. Heiden for valuable help with the CDD BLAST analyses.This study was financially supported by the SAW-funded ATKiM project, which provided funds to D. P. R. Herlemann, C. Meeske, K. Jürgens, S. Markert, and T. Schweder. D. P. R. Herlemann was also supported by the European Regional Develop- ment Fund/Estonian Research Council funded Mobilitas Plus Top Researcher grant MOBTT24. We thank the crew and captain of the RV Meteor (M86, M87) for support during the research cruise. The computations were performed on resources provided by the Swedish National Infrastructure for Computing (SNIC) at the PDC Centre for High Performance Computing (PDC-HPC) and Uppsala Multidisciplinary Center for Advanced Computational Science (UPPMAX). We thank Jana Matulla for excellent technical assis- tance and Stephan Fuchs for his help and advice in MS database construction. We also thank Stefan E. Heiden for valuable help with the CDD BLAST analyses

Comparative proteomics of related symbiotic mussel species reveals high variability of host-symbiont interactions.

Deep-sea Bathymodiolus mussels and their chemoautotrophic symbionts are well-studied representatives of mutualistic host-microbe associations. However, how host-symbiont interactions vary on the molecular level between related host and symbiont species remains unclear. Therefore, we compared the host and symbiont metaproteomes of Pacific B. thermophilus, hosting a thiotrophic symbiont, and Atlantic B. azoricus, containing two symbionts, a thiotroph and a methanotroph. We identified common strategies of metabolic support between hosts and symbionts, such as the oxidation of sulfide by the host, which provides a thiosulfate reservoir for the thiotrophic symbionts, and a cycling mechanism that could supply the host with symbiont-derived amino acids. However, expression levels of these processes differed substantially between both symbioses. Backed up by genomic comparisons, our results furthermore revealed an exceptionally large repertoire of attachment-related proteins in the B. thermophilus symbiont. These findings imply that host-microbe interactions can be quite variable, even between closely related systems

Stationäre und intensivmedizinische Versorgungsstrukturen von COVID-19-Patienten bis Juli 2020

Hintergrund Hospitalisierte COVID-19-Patienten weisen eine hohe Morbidität und Mortalität auf und sind häufig auf eine intensivstationäre Behandlung und hier vor allem auf eine Beatmungstherapie angewiesen. Bisher ist wenig über die Patientenallokation bekannt. Ziel der Arbeit Die Darstellung der Strukturen der Krankenhausversorgung der COVID-19-Patienten zwischen dem 26. Februar bis zum 31. Juli 2020 Daten und Methoden Für die Analyse der Versorgungsstrukturen wurden die Abrechnungsdaten der Allgemeinen Ortskrankenkassen (AOK) ausgewertet. Es wurden ausschließlich abgeschlossene somatische COVID-19-Fälle ausgewertet, bei denen das Virus durch einen Labortest nachgewiesen wurde. Die Stichprobe umfasst 17.094 COVID-19-Fälle, deren Behandlung in 1082 Krankenhäusern erfolgte. Ergebnisse An der Versorgung der COVID-19-Fälle waren 77 % aller Krankenhäuser beteiligt, an der intensivmedizinischen Behandlung 48 % aller Krankenhäuser. Von den Krankenhäusern, die COVID-19-Fälle behandelt haben, versorgte eine Hälfte 88 % aller Fälle. Das deutet zwar auf einen Zentrierungseffekt der COVID-19-Fälle auf bestimmte Krankenhäuser hin, jedoch verteilten sich die übrigen 12 % der Fälle auf viele Krankenhäuser mit oftmals sehr kleinen Fallzahlen. Des Weiteren wurde knapp ein Viertel der beatmeten COVID-19-Fälle in Krankenhäusern behandelt, die eine unterdurchschnittliche Beatmungserfahrung aufweisen. Diskussion Im Rahmen steigender Infektionszahlen ist es sowohl notwendig die Versorgungsstrukturen von COVID-19-Fällen durch klar definierte und zentral gesteuerte Stufenkonzepte zu verbessern als auch die Versorgung der Patienten ohne COVID-19 weiterhin aufrechtzuerhalten. Ein umfassendes Stufenkonzept mit stärkerer Konzentration erscheint für die Versorgung dieser komplex erkrankten Patienten sinnvoll.Background Hospitalized coronavirus disease 2019 (COVID-19) patients have a high morbidity and mortality and are often dependent on intensive care, especially mechanical ventilation. Little is as yet known about COVID-19 patient allocation. Objectives Analysis of the structures of German hospital care for COVID-19 patients up to July 2020 in terms of number of beds and previous ventilation experience. Data and methods For the analysis of the care structures, only completed COVID-19 cases in which the virus was detected by a PCR test were evaluated. Claims data from the German Local Health Care Funds (Allgemeine Ortskrankenkassen, AOK) were analysed. The sample includes 17,094 COVID-19 cases that were treated in 1082 hospitals. Results A total of 77% of all hospitals participated in the treatment COVID-19 patients and 48% of all hospitals provided intensive care for these patients. One half of the hospitals that treated COVID-19 cases cared for 88% of all cases. Although this suggests a centralization effect of COVID-19 cases in specific hospitals, the remaining 12% of the cases were distributed among many hospitals with often very small numbers of cases. Furthermore, 23% of the ventilated COVID-19 cases were treated in hospitals with below-average ventilation experience. Conclusions In the context of increasing numbers of infections, it is both necessary to improve the allocation of hospitalized, and therefore potentially ventilated, COVID-19 cases by means of clearly defined and centrally controlled pyramid-type concepts and to continue to care for patients without COVID-19. For Germany, a comprehensive pyramid-type concept with a greater concentration in the best-qualified hospitals seems reasonable for the care of these patients with complex diseases.TU Berlin, Open-Access-Mittel – 202