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To date, very little is known about the bacterial core community of marine sediments. Here we study the environmental distribution, abundance and ecogenomics of the gammaproteobacterial Woeseiaceae /JTB255 marine benthic group. A meta-analysis of published work shows that the Woeseiaceae /JTB255 are ubiquitous and consistently rank among the most abundant 16S rRNA gene sequences in diverse marine sediments. They account for up to 22% of bacterial amplicons and 6% of total cell counts in European and Australian coastal sediments. The analysis of a single-cell genome, metagenomic bins and the genome of the next cultured relative Woeseia oceani indicated a broad physiological range, including heterotrophy and facultative autotrophy. All tested (meta)genomes encode a truncated denitrification pathway to nitrous oxide. The broad range of energy-yielding metabolisms possibly explains the ubiquity and high abundance of Woeseiaceae /JTB255 in marine sediments, where they carry out diverse, but yet unknown ecological functions.

A process of global importance in carbon cycling is the remineralization of algae biomass by heterotrophic bacteria, most notably during massive marine algae blooms. Such blooms can trigger secondary blooms of planktonic bacteria that consist of swift successions of distinct bacterial clades, most prominently members of the Flavobacteriia, Gammaproteobacteria and the alphaproteobacterial Roseobacter clade. We investigated such successions during spring phytoplankton blooms in the southern North Sea (German Bight) for four consecutive years. Dense sampling and high-resolution taxonomic analyses allowed the detection of recurring patterns down to the genus level. Metagenome analyses also revealed recurrent patterns at the functional level, in particular with respect to algal polysaccharide degradation genes. We, therefore, hypothesize that even though there is substantial inter-annual variation between spring phytoplankton blooms, the accompanying succession of bacterial clades is largely governed by deterministic principles such as substrate-induced forcing. Small algae in the world's oceans remove about as much carbon dioxide from the atmosphere as land plants. These algae do not grow continuously, but often surge in numbers during temporary blooms. Such blooms can be large enough to be seen from space by satellites. The lifespan of algae within such blooms is short, and when they die, marine bacteria feed on the remnants, which releases much of the stored carbon dioxide. Much of an algal cell consists of different types of polysaccharides. These large molecules are essentially made from sugars linked together. Polysaccharides are varied molecules and can contain many different sugars that can be linked in a number of different ways. During algae blooms bacteria proliferate that are specialized in the degradation of these polysaccharides. In 2012, researchers reported how over the progression of an algae bloom different groups of marine bacteria bloomed in rapid succession. However, it remained unknown whether the same or different groups of bacteria respond to algae blooms at the same place from year to year, and whether or not these bacteria use the same enzymes to degrade the polysaccharides. Teeling, Fuchs et al. – who include many of the researchers from the 2012 study – now report on the analysis of a series of algae blooms that occurred in the southern North Sea between 2009 and 2012. The analysis is based on samples collected every week during the spring seasons, and shows that certain groups of related bacteria, known as clades, became common during each bloom. Teeling, Fuchs et al. also found indications that the clades that repeatedly occurred had similar sets of genes for degrading algal polysaccharides, but that the sets were different between the clades. These data suggest that there is a specialized bacterial community that together can degrade the complex mixture of algal polysaccharides during blooms. This community reappears each year with an unexpectedly low level of variation. Since different species of algae made up the blooms in each year, this finding suggests that the major polysaccharides in these algae are similar or even identical. Future work will focus on the specific activities of bacterial enzymes that are needed to degrade polysaccharides during algae blooms. Study of these enzymes in the laboratory will help to resolve, which polysaccharides are attacked in which manner, and to ultimately help to identify the most abundant algal polysaccharides. This will improve our current understanding of the carbon cycle in the world’s oceans.

We investigated Bacteroidetes during spring algae blooms in the southern North Sea in 2010–2012 using a time series of 38 deeply sequenced metagenomes. Initial partitioning yielded 6455 bins, from which we extracted 3101 metagenome-assembled genomes (MAGs) including 1286 Bacteroidetes MAGs covering ~120 mostly uncultivated species. We identified 13 dominant, recurrent Bacteroidetes clades carrying a restricted set of conserved polysaccharide utilization loci (PULs) that likely mediate the bulk of bacteroidetal algal polysaccharide degradation. The majority of PULs were predicted to target the diatom storage polysaccharide laminarin, alpha-glucans, alpha-mannose-rich substrates, and sulfated xylans. Metaproteomics at 14 selected points in time revealed expression of SusC-like proteins from PULs targeting all of these substrates. Analyses of abundant key players and their PUL repertoires over time furthermore suggested that fewer and simpler polysaccharides dominated early bloom stages, and that more complex polysaccharides became available as blooms progressed.

Marine algae convert a substantial fraction of fixed carbon dioxide into various polysaccharides. Flavobacteriia that are specialized on algal polysaccharide degradation feature genomic clusters termed polysaccharide utilization loci (PULs). As knowledge on extant PUL diversity is sparse, we sequenced the genomes of 53 North Sea Flavobacteriia and obtained 400 PULs. Bioinformatic PUL annotations suggest usage of a large array of polysaccharides, including laminarin, α-glucans, and alginate as well as mannose-, fucose-, and xylose-rich substrates. Many of the PULs exhibit new genetic architectures and suggest substrates rarely described for marine environments. The isolates’ PUL repertoires often differed considerably within genera, corroborating ecological niche-associated glycan partitioning. Polysaccharide uptake in Flavobacteriia is mediated by SusCD-like transporter complexes. Respective protein trees revealed clustering according to polysaccharide specificities predicted by PUL annotations. Using the trees, we analyzed expression of SusC/D homologs in multiyear phytoplankton bloom-associated metaproteomes and found indications for profound changes in microbial utilization of laminarin, α-glucans, β-mannan, and sulfated xylan. We hence suggest the suitability of SusC/D-like transporter protein expression within heterotrophic bacteria as a proxy for the temporal utilization of discrete polysaccharides.

Massive releases of organic substrates during marine algal blooms trigger growth of many clades of heterotrophic bacteria. Algal polysaccharides represent the most diverse and structurally complex class of these substrates, yet their role in shaping the microbial community composition is poorly understood. We investigated, whether polysaccharide utilization capabilities contribute to niche differentiation of Polaribacter spp. (class Flavobacteriia ; known to include relevant polysaccharide-degraders) that were abundant during 2009–2012 spring algal blooms in the southern North Sea. We identified six distinct Polaribacter clades using phylogenetic and phylogenomic analyses, quantified their abundances via fluorescence in situ hybridization, compared metagenome-assembled genomes, and assessed in situ gene expression using metaproteomics. Four clades with distinct polysaccharide niches were dominating. Polaribacter 2-a comprised typical first responders featuring small genomes with limited polysaccharide utilization capacities. Polaribacter 3-a were abundant only in 2010 and possessed a distinct sulfated α-glucoronomannan degradation potential. Polaribacter 3-b responded late in blooms and had the capacity to utilize sulfated xylan. Polaribacter 1-a featured high numbers of glycan degradation genes and were particularly abundant following Chattonella algae blooms. These results support the hypothesis that sympatric Polaribacter clades occupy distinct glycan niches during North Sea spring algal blooms.

Social prescribing (SP) aims to provide targeted psychosocial support and close the gap between medical and non-medical services. This review assesses the effectiveness of community-based SP interventions. We performed a systematic review and qualitative synthesis of interventional studies of community referral interventions focused on facilitating psychosocial support. We considered health-related endpoints, other patient reported outcomes, or health care utilization. Six databases, grey literature, and additional trials registers were searched. Results were screened in a two-step process, followed by data extraction, each by two independent reviewers. If data permitted such, effect sizes were calculated. Risk of bias was assessed with the EPHPP and the Cochrane RoB2 tools. We identified 68 reports from 53 different projects, three were controlled studies. Uncontrolled studies with shorter time frames frequently reported positive effects. This could largely not be seen in controlled settings and for longer follow-up periods. Designs, populations, and outcomes evaluated were heterogeneous with high risk of bias for most studies. Current evidence suggests positive effects of SP on a variety of relevant endpoints. Due to quality deficits in the available studies, scope for conclusions concerning clinical relevance and sustainability is limited. Further methodologically rigorous controlled trials are needed.

Background Over the past years, sequencing technologies have expanded our ability to examine novel microbial metabolisms and diversity previously obscured by isolation approaches. Long-read sequencing promises to revolutionize the metagenomic field and recover less fragmented genomes from environmental samples. Nonetheless, how to best benefit from long-read sequencing and whether long-read sequencing can provide recovered genomes of similar characteristics as short-read approaches remains unclear. Results We recovered metagenome-assembled genomes (MAGs) from the free-living fraction at four-time points during a spring bloom in the North Sea. The taxonomic composition of all MAGs recovered was comparable between technologies. However, differences consisted of higher sequencing depth for contigs and higher genome population diversity in short-read compared to long-read metagenomes. When pairing population genomes recovered from both sequencing approaches that shared ≥ 99% average nucleotide identity, long-read MAGs were composed of fewer contigs, a higher N50, and a higher number of predicted genes when compared to short-read MAGs. Moreover, 88% of the total long-read MAGs carried a 16S rRNA gene compared to only 23% of MAGs recovered from short-read metagenomes. Relative abundances for population genomes recovered using both technologies were similar, although disagreements were observed for high and low GC content MAGs. Conclusions Our results highlight that short-read technologies recovered more MAGs and a higher number of species than long-read due to an overall higher sequencing depth. Long-read samples produced higher quality MAGs and similar species composition compared to short-read sequencing. Differences in the GC content recovered by each sequencing technology resulted in divergences in the diversity recovered and relative abundance of MAGs within the GC content boundaries.

Background The development of clinical guidelines aimed at GPs is a key strategy to improving the management of chronic kidney disease (CKD). In 2019, the first CKD guideline aimed specifically at GPs practicing in Germany was published by the German College of General Practitioners and Family Physicians (DEGAM.) Aims The aim of this study is to identify the barriers and enablers for the implementation of this guideline. The results of this project, together with quantitative evaluation against quality indicators for CKD in primary care will inform an update to the guideline. Methods We performed 17 semi-structured interviews with GPs practicing in Berlin and Brandenburg. Transcripts were analysed using qualitative content analysis as described by Mayring. Results We found that the perception of low clinical priority of CKD compared to other chronic diseases, opportunity cost of using guidelines, as well as poor patient understanding were significant barriers. GPs expressed that improved graphic design or integration of guideline recommendations in clinical decision support systems were enabling factors. Clinical problems concerning CKD were mostly solved by recourse to informal communication with specialists. GPs reported that they rarely consulted CKD guidelines as an aide to clinical decision making. Conclusion The most significant barrier to use was that guidelines were not used as step-by-step decision aide in consultations with patients. Our analysis suggests that informal contact between primary and secondary care is significant conduit for evidence-based information on CKD in German primary care. Implementation projects should support the development of these relationships.

Cardan angle sequences are widely used to describe three-dimensional joint rotations in the foot and ankle, but differences in rotation order can complicate interpretation, especially in joints with multiplanar motion. This study systematically evaluated the influence of Cardan sequence selection on the kinematics of the tibiotalar, talofibular, tibiofibular, subtalar, and talonavicular joints using both in vivo biplane fluoroscopy gait analysis and in vitro passive joint kinematic data from robotic cadaveric simulation. Six Cardan sequences were evaluated to quantify their effects on joint angle profiles and range of motion. Tibiotalar, talofibular, and tibiofibular joint kinematics were largely consistent across Cardan sequences, supporting continued use of the ISB-recommended XYZ sequence (dorsiflexion/plantarflexion followed by inversion/eversion followed by internal/external rotation). Subtalar and talonavicular joint kinematics exhibited substantial sequence-dependent variations in reported joint angles during gait, prescribed tibial external/internal rotation, and prescribed tibial varus/valgus alignment motions. Sequences prioritizing the Y-axis (inversion/eversion) or Z-axis (internal/external rotation) produced the most significant differences relative to the XYZ sequence. Based on joint- and motion-specific sensitivity, we recommend the XYZ sequence for the tibiotalar, talofibular, and tibiofibular joints; YZX, ZXY, or ZYX sequences for prioritizing transverse subtalar joint motion and XYZ or XZY sequences for coronal subtalar joint motion; and XYZ, XZY, or YXZ sequences for sagittal and transverse talonavicular joint motion, with YZX sequence for coronal talonavicular joint motion. These findings highlight the importance of joint-specific rotation sequence selection to improve consistency, reduce crosstalk, and enhance the clinical relevance of foot and ankle kinematic analyses.