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1.
J Wound Ostomy Continence Nurs ; 51(4): 303-311, 2024.
Article in English | MEDLINE | ID: mdl-39037163

ABSTRACT

PURPOSE: The purpose of the study was to investigate the fit of a two-piece pouching system with a concave-shaped skin barrier on people with an outward peristomal body profile and its effect on leakage, wear time, and quality of life (QoL) related to using an ostomy product. DESIGN: Randomized, controlled, open-label, cross-over trial. SUBJECTS AND SETTINGS: The sample comprised 53 subjects with outward peristomal body profiles and problems with leakage of ostomy effluent from their pouching system. Participants were randomized to the concave two-piece pouching system or a comparator (two-piece pouching system with a flat skin barrier) for 3 weeks. Subjects were then crossed over to the opposite skin barrier for an additional 3 weeks. The study was conducted in Denmark, Norway, Germany, and the Netherlands; data were collected in multiple ambulatory clinics or during home visits. METHODS: The primary end point was the ability of the skin barrier to fit body contours; secondary outcomes were leakage of effluent from the pouching system, wear time, and QoL related to using an ostomy product via the validated Ostomy-Q questionnaire. Primary comparisons between concave and comparator pouching systems were evaluated using proportional odds models and mixed models taking test period into account. RESULTS: Analysis included randomized subjects who had been exposed to at least one product and with information on at least one end point (full-analysis-set, n = 52). The concave pouching system provided a better fit to body contours than the comparator (P< .001) and reduced the degree of leakage underneath the skin barrier (LS mean difference = -1.84, 95% CI -3.31 to -0.37; P = .016). Participants experienced fewer episodes of leakage outside the skin barrier when using concave versus comparator pouching system (13.0% vs. 26.7%, respectively). Participants reported significant improvements in QoL (LS mean difference = 14.3; 95% CI 9.4 to 19.2; P < .001). No significant difference in wear time between skin barrier shapes was reported. CONCLUSIONS: Study findings indicate that a pouching system with a concave skin barrier achieved a better body fit on people with an outward peristomal body profile and resulted in fewer leakage incidents and higher QoL compared to using a pouching system with a flat skin barrier.


Subject(s)
Cross-Over Studies , Quality of Life , Humans , Quality of Life/psychology , Male , Female , Middle Aged , Aged , Adult , Netherlands , Ostomy/methods , Ostomy/adverse effects , Ostomy/instrumentation , Denmark , Germany , Norway , Surveys and Questionnaires , Surgical Stomas/adverse effects
3.
J Am Chem Soc ; 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39016546

ABSTRACT

The germanosilicide Na4-xGeySi16-y (0.4 ≤ x ≤ 1.1, 4.7 ≤ y ≤ 9.3) was synthesized under high-pressure, high-temperature conditions. The novel guest-host compound comprises a unique tetrel framework with dual channels housing sodium and smaller, empty (Si,Ge)9 units. The arrangement represents a new structure type with an overall structural topology that is closely related to a hypothetical carbon allotrope. Topological analysis of the structure revealed that the guest environment space cannot be tiled with singular polyhedra as in cage compounds (e.g., clathrates). The analysis of natural tilings provides a convenient method to unambiguously compare related tetrel-rich structures and can help elucidate new possible structural arrangements of intermetallic compounds.

4.
Neurosci Conscious ; 2024(1): niae026, 2024.
Article in English | MEDLINE | ID: mdl-38895541

ABSTRACT

A recent advancement in consciousness science has been the introduction of a multidimensional framework of consciousness. This framework has been applied to global states of consciousness, including psychedelic states and disorders of consciousness, and the consciousness of non-human animals. The multidimensional framework enables a finer parsing of both various states of consciousness and forms of animal consciousness, paving the way for new scientific investigations into consciousness. In this paper, the multidimensional model is expanded by constructing temporal profiles. This expansion allows for the modelling of changes in consciousness across the life cycles of organisms and the progression over time of disorders of consciousness. The result of this expansion is 2-fold: (i) it enables new modes of comparison, both across stages of development and across species; (ii) it proposes that more attention be given to the various types of fluctuations that occur in patients who are suffering from disorders of consciousness.

5.
Ugeskr Laeger ; 186(25)2024 Jun 17.
Article in Danish | MEDLINE | ID: mdl-38904284

ABSTRACT

This review delves into the application and effectiveness of Very Brief Advice (VBA) for smoking cessation in Denmark's healthcare system. Despite some evidence, VBA's support remains limited, adopted by only a few hospitals and overlooked by many healthcare professionals. To enhance cessation efforts, we recommend elevating its status from optional to mandatory. Underlining VBA's significance as a referral catalyst is pivotal to ensuring its sustained influence within the broader cessation strategy.


Subject(s)
Smoking Cessation , Smoking Cessation/methods , Humans , Denmark , Counseling , Referral and Consultation
6.
J Bacteriol ; 206(6): e0016224, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38814092

ABSTRACT

Reducing growth and limiting metabolism are strategies that allow bacteria to survive exposure to environmental stress and antibiotics. During infection, uropathogenic Escherichia coli (UPEC) may enter a quiescent state that enables them to reemerge after the completion of successful antibiotic treatment. Many clinical isolates, including the well-characterized UPEC strain CFT073, also enter a metabolite-dependent, quiescent state in vitro that is reversible with cues, including peptidoglycan-derived peptides and amino acids. Here, we show that quiescent UPEC is antibiotic tolerant and demonstrate that metabolic flux in the tricarboxylic acid (TCA) cycle regulates the UPEC quiescent state via succinyl-CoA. We also demonstrate that the transcriptional regulator complex integration host factor and the FtsZ-interacting protein ZapE, which is important for E. coli division during stress, are essential for UPEC to enter the quiescent state. Notably, in addition to engaging FtsZ and late-stage cell division proteins, ZapE also interacts directly with TCA cycle enzymes in bacterial two-hybrid assays. We report direct interactions between the succinate dehydrogenase complex subunit SdhC, the late-stage cell division protein FtsN, and ZapE. These interactions may enable communication between oxidative metabolism and the cell division machinery in UPEC. Moreover, these interactions are conserved in an E. coli K-12 strain. This work suggests that there is coordination among the two fundamental and essential pathways that regulate overall growth, quiescence, and antibiotic susceptibility. IMPORTANCE: Uropathogenic Escherichia coli (UPEC) are the leading cause of urinary tract infections (UTIs). Upon invasion into bladder epithelial cells, UPEC establish quiescent intracellular reservoirs that may lead to antibiotic tolerance and recurrent UTIs. Here, we demonstrate using an in vitro system that quiescent UPEC cells are tolerant to ampicillin and have decreased metabolism characterized by succinyl-CoA limitation. We identify the global regulator integration host factor complex and the cell division protein ZapE as critical modifiers of quiescence and antibiotic tolerance. Finally, we show that ZapE interacts with components of both the cell division machinery and the tricarboxylic acid cycle, and this interaction is conserved in non-pathogenic E. coli, establishing a novel link between cell division and metabolism.


Subject(s)
Anti-Bacterial Agents , Citric Acid Cycle , Escherichia coli Proteins , Gene Expression Regulation, Bacterial , Uropathogenic Escherichia coli , Uropathogenic Escherichia coli/metabolism , Uropathogenic Escherichia coli/genetics , Uropathogenic Escherichia coli/drug effects , Uropathogenic Escherichia coli/growth & development , Anti-Bacterial Agents/pharmacology , Escherichia coli Proteins/metabolism , Escherichia coli Proteins/genetics , Citric Acid Cycle/drug effects , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Drug Resistance, Bacterial , Escherichia coli Infections/microbiology
7.
Immunity ; 57(7): 1514-1532.e15, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38788712

ABSTRACT

Receptor-interacting serine/threonine-protein kinase 1 (RIPK1) functions as a critical stress sentinel that coordinates cell survival, inflammation, and immunogenic cell death (ICD). Although the catalytic function of RIPK1 is required to trigger cell death, its non-catalytic scaffold function mediates strong pro-survival signaling. Accordingly, cancer cells can hijack RIPK1 to block necroptosis and evade immune detection. We generated a small-molecule proteolysis-targeting chimera (PROTAC) that selectively degraded human and murine RIPK1. PROTAC-mediated depletion of RIPK1 deregulated TNFR1 and TLR3/4 signaling hubs, accentuating the output of NF-κB, MAPK, and IFN signaling. Additionally, RIPK1 degradation simultaneously promoted RIPK3 activation and necroptosis induction. We further demonstrated that RIPK1 degradation enhanced the immunostimulatory effects of radio- and immunotherapy by sensitizing cancer cells to treatment-induced TNF and interferons. This promoted ICD, antitumor immunity, and durable treatment responses. Consequently, targeting RIPK1 by PROTACs emerges as a promising approach to overcome radio- or immunotherapy resistance and enhance anticancer therapies.


Subject(s)
Immunogenic Cell Death , Proteolysis , Receptor-Interacting Protein Serine-Threonine Kinases , Signal Transduction , Receptor-Interacting Protein Serine-Threonine Kinases/metabolism , Humans , Animals , Mice , Proteolysis/drug effects , Cell Line, Tumor , Signal Transduction/drug effects , Immunogenic Cell Death/drug effects , Necroptosis/drug effects , Necroptosis/immunology , Neoplasms/immunology , Neoplasms/drug therapy , Mice, Inbred C57BL , Antineoplastic Agents/pharmacology , Immunotherapy/methods
8.
J Zoo Wildl Med ; 55(1): 173-181, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38453500

ABSTRACT

Detailed knowledge of biological variation can facilitate accurate interpretation of clinical pathology parameters. A recent biological variation study in Asian elephants (Elephas maximus) found that hematology parameters had high individuality, which suggests that population-derived reference intervals may be an insensitive diagnostic tool. In elephant medicine, sensitive hematology-related diagnostics are crucial for clinical decision-making, particularly in elephants at risk for elephant endotheliotropic herpesvirus hemorrhagic disease (EEHV-HD). The objective of this study was to assess biological variation of hematology parameters in African elephants to determine whether population-derived reference intervals are a sensitive diagnostic tool for interpreting results and to provide a useful alternative. Eight healthy African elephants had blood collected under behavioral training every other week for 8 wk. Complete blood cell count (CBC) analysis was performed in duplicate to assess analytical variation. Previous methods were used to determine between-individual variation, within-individual variation, index of individuality, and reference change values (RCV). This study found that most hematology parameters displayed intermediate-to-high individuality, which suggests that alternatives to population-derived reference intervals are necessary to detect pathologic changes. To test the results of our biological variation data, a case of EEHV-HD was retrospectively evaluated. Individual normal values and calculated RCV detected a clinically significant monocytopenia, leukopenia, and thrombocytopenia associated with EEHV2 viremia. However, none of these parameters fell outside a population-derived reference interval. This study highlights the utility of biological variation in clinical decision-making and demonstrates that individual normal values and RCV may be important diagnostic tools for CBC interpretation in African elephants.


Subject(s)
Elephants , Hematology , Herpesviridae Infections , Herpesviridae , Animals , Herpesviridae Infections/veterinary , Retrospective Studies
9.
EMBO J ; 43(6): 904-930, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38337057

ABSTRACT

Mitochondrial outer membrane permeabilisation (MOMP) is often essential for apoptosis, by enabling cytochrome c release that leads to caspase activation and rapid cell death. Recently, MOMP has been shown to be inherently pro-inflammatory with emerging cellular roles, including its ability to elicit anti-tumour immunity. Nonetheless, how MOMP triggers inflammation and how the cell regulates this remains poorly defined. We find that upon MOMP, many proteins localised either to inner or outer mitochondrial membranes are ubiquitylated in a promiscuous manner. This extensive ubiquitylation serves to recruit the essential adaptor molecule NEMO, leading to the activation of pro-inflammatory NF-κB signalling. We show that disruption of mitochondrial outer membrane integrity through different means leads to the engagement of a similar pro-inflammatory signalling platform. Therefore, mitochondrial integrity directly controls inflammation, such that permeabilised mitochondria initiate NF-κB signalling.


Subject(s)
NF-kappa B , Ubiquitin , Humans , NF-kappa B/genetics , NF-kappa B/metabolism , Ubiquitin/metabolism , Mitochondrial Membranes/metabolism , Mitochondria/metabolism , Apoptosis/physiology , Inflammation/metabolism
10.
APMIS ; 132(3): 210-220, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38270387

ABSTRACT

This study aimed to develop and validate "the Imprint method,", a technique for sampling microbes from chronic wounds while preserving their two-dimensional spatial organization. We used nylon filters to sample bacteria and compared with sampling using Eswabs in 12 patients. The Imprint method identified a mean of 0.93 unique species more than Eswab (4.3 ± 2.2 and 3.4 ± 1.4 unique species, respectively; mean ± SD; n = 30). Accuracy between the Eswab and the Imprint method was 93.2% and in cases of disagreement between methods, Imprint had a higher sensitivity in 6/8 of the most prevalent species. In vitro validation confirmed that the Imprint method could transfer bacterial colonies while replicating their two-dimensional organization and the area covered by bacteria on the plate sampled. Clinical testing demonstrated that the imprint method is a rapid and feasible technique that identified more unique bacterial species than Eswab with a good agreement between methods but that Imprint was better at detecting important pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa. The Imprint method is a novel technique that cultures and records the two-dimensional organization of microbes, providing an alternative or supplement to conventional surface culture using Eswab.


Subject(s)
Bacteria , Staphylococcal Infections , Humans , Staphylococcus aureus , Specimen Handling/methods , Staphylococcal Infections/microbiology , Pseudomonas aeruginosa
11.
Inorg Chem ; 62(31): 12203-12212, 2023 Aug 07.
Article in English | MEDLINE | ID: mdl-37487202

ABSTRACT

The MSb2 compounds with M = Cr, Fe, Ru, and Os have been investigated under high pressures by synchrotron powder X-ray diffraction. All compounds, except CrSb2, were found to retain the marcasite structure up to the highest pressures (more than 50 GPa). In contrast, we found that CrSb2 has a structural phase transition around 10 GPa to a metastable, MoP2-type structure with Cr coordinated to seven Sb atoms. In addition, we compared ambient temperature compression with laser-heating experiments and found that laser-heating at pressures below and above this phase transition results in the known CuAl2-type structure. Density functional theory calculations show that this tetragonal structure is the most stable in the whole pressure interval. However, a crossing of the marcasite's and MoP2-like structure's enthalpies occurs between 5 and 7.5 GPa, which is in good agreement with the experimental data. The phase transition to the MoP2-type structure observed in this work opens up for discovering other compounds with this new transition pathway from the marcasite structure.

12.
Biofilm ; 5: 100119, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37131492

ABSTRACT

Many companies in the food industry apply reverse osmosis (RO) membranes to ensure high-quality reuse of water. Biofouling is however, a common, recalcitrant and recurring problem that blocks transport over membranes and decreases the water recovery. Microorganisms adhering to membranes may form biofilm and produce an extracellular matrix, which protects against external stress and ensures continuous attachment. Thus, various agents are tested for their ability to degrade and disperse biofilms. Here, we identified industrially relevant bacterial model communities that form biofilms on RO membranes used for treating process water before reuse. There was a marked difference in the biofilm forming capabilities of bacteria isolated from contaminated RO membranes. One species, Raoultella ornithinolytica, was particularly capable of forming biofilm and was included in most communities. The potential of different enzymes (Trypsin-EDTA, Proteinase K, α-Amylase, ß-Mannosidase and Alginate lyase) as biofouling dispersing agents was evaluated at different concentrations (0.05 U/ml and 1.28 U/ml). Among the tested enzymes, ß-Mannosidase was the only enzyme able to reduce biofilm formation significantly within 4 h of exposure at 25 °C (0.284 log reduction), and only at the high concentration. Longer exposure duration, however, resulted in significant biofilm reduction by all enzymes tested (0.459-0.717 log reduction) at both low and high concentrations. Using confocal laser scanning microscopy, we quantified the biovolume on RO membranes after treatment with two different enzyme mixtures. The application of proteinase K and ß-Mannosidase significantly reduced the amount of attached biomass (43% reduction), and the combination of all five enzymes showed even stronger reducing effect (71% reduction). Overall, this study demonstrates a potential treatment strategy, using matrix-degrading enzymes for biofouled RO membranes in food processing water treatment streams. Future studies on optimization of buffer systems, temperature and other factors could facilitate cleaning operations based on enzymatic treatment extending the lifespan of membranes with a continuous flux.

14.
EMBO Rep ; 23(12): e55839, 2022 12 06.
Article in English | MEDLINE | ID: mdl-36268590

ABSTRACT

ZBP1 is an interferon-induced cytosolic nucleic acid sensor that facilitates antiviral responses via RIPK3. Although ZBP1-mediated programmed cell death is widely described, whether and how it promotes inflammatory signaling is unclear. Here, we report a ZBP1-induced inflammatory signaling pathway mediated by K63- and M1-linked ubiquitin chains, which depends on RIPK1 and RIPK3 as scaffolds independently of cell death. In human HT29 cells, ZBP1 associated with RIPK1 and RIPK3 as well as ubiquitin ligases cIAP1 and LUBAC. ZBP1-induced K63- and M1-linked ubiquitination of RIPK1 and ZBP1 to promote TAK1- and IKK-mediated inflammatory signaling and cytokine production. Inhibition of caspase activity suppressed ZBP1-induced cell death but enhanced cytokine production in a RIPK1- and RIPK3 kinase activity-dependent manner. Lastly, we provide evidence that ZBP1 signaling contributes to SARS-CoV-2-induced cytokine production. Taken together, we describe a ZBP1-RIPK3-RIPK1-mediated inflammatory signaling pathway relayed by the scaffolding role of RIPKs and regulated by caspases, which may induce inflammation when ZBP1 is activated below the threshold needed to trigger a cell death response.


Subject(s)
Cell Death , RNA-Binding Proteins , Receptor-Interacting Protein Serine-Threonine Kinases , Humans , Cytokines , Receptor-Interacting Protein Serine-Threonine Kinases/genetics , Signal Transduction , Ubiquitin , RNA-Binding Proteins/genetics , HT29 Cells , Inflammation
15.
NPJ Biofilms Microbiomes ; 8(1): 59, 2022 07 20.
Article in English | MEDLINE | ID: mdl-35858930

ABSTRACT

The majority of ecological, industrial and medical impacts of bacteria result from diverse communities containing multiple species. This diversity presents a significant challenge as co-cultivation of multiple bacterial species frequently leads to species being outcompeted and, with this, the possibility to manipulate, evolve and improve bacterial communities is lost. Ecological theory predicts that a solution to this problem will be to grow species in structured environments, which reduces the likelihood of competitive exclusion. Here, we explored the ability of cultivation in a structured environment to facilitate coexistence, evolution, and adaptation in an industrially important community: Lactococcus lactis and Leuconostoc mesenteroides frequently used as dairy starter cultures. As commonly occurs, passaging of these two species together in a liquid culture model led to the loss of one species in 6 of 20 lineages (30%). By contrast, when we co-cultured the two species as biofilms on beads, a stable coexistence was observed in all lineages studied for over 100 generations. Moreover, we show that the co-culture drove evolution of new high-yield variants, which compared to the ancestor grew more slowly, yielded more cells and had enhanced capability of biofilm formation. Importantly, we also show that these high-yield biofilm strains did not evolve when each species was passaged in monoculture in the biofilm model. Therefore, both co-culture and the biofilm model were conditional for these high-yield strains to evolve. Our study underlines the power of ecological thinking-namely, the importance of structured environments for coexistence-to facilitate cultivation, evolution, and adaptation of industrially important bacterial communities.


Subject(s)
Biofilms , Lactococcus lactis , Bacteria , Lactococcus lactis/genetics
16.
Article in English | MEDLINE | ID: mdl-35552141

ABSTRACT

Image translation with convolutional autoencoders has recently been used as an approach to multimodal change detection (CD) in bitemporal satellite images. A main challenge is the alignment of the code spaces by reducing the contribution of change pixels to the learning of the translation function. Many existing approaches train the networks by exploiting supervised information of the change areas, which, however, is not always available. We propose to extract relational pixel information captured by domain-specific affinity matrices at the input and use this to enforce alignment of the code spaces and reduce the impact of change pixels on the learning objective. A change prior is derived in an unsupervised fashion from pixel pair affinities that are comparable across domains. To achieve code space alignment, we enforce pixels with similar affinity relations in the input domains to be correlated also in code space. We demonstrate the utility of this procedure in combination with cycle consistency. The proposed approach is compared with the state-of-the-art machine learning and deep learning algorithms. Experiments conducted on four real and representative datasets show the effectiveness of our methodology.

17.
FEMS Microbiol Rev ; 46(5)2022 09 02.
Article in English | MEDLINE | ID: mdl-35640890

ABSTRACT

The microbial world represents a phenomenal diversity of microorganisms from different kingdoms of life, which occupy an impressive set of ecological niches. Most, if not all, microorganisms once colonize a surface develop architecturally complex surface-adhered communities, which we refer to as biofilms. They are embedded in polymeric structural scaffolds and serve as a dynamic milieu for intercellular communication through physical and chemical signalling. Deciphering microbial ecology of biofilms in various natural or engineered settings has revealed coexistence of microorganisms from all domains of life, including Bacteria, Archaea, and Eukarya. The coexistence of these dynamic microbes is not arbitrary, as a highly coordinated architectural setup and physiological complexity show ecological interdependence and myriads of underlying interactions. In this review, we describe how species from different kingdoms interact in biofilms and discuss the functional consequences of such interactions. We highlight metabolic advances of collaboration among species from different kingdoms, and advocate that these interactions are of great importance and need to be addressed in future research. Since trans-kingdom biofilms impact diverse contexts, ranging from complicated infections to efficient growth of plants, future knowledge within this field will be beneficial for medical microbiology, biotechnology, and our general understanding of microbial life in nature.


Subject(s)
Archaea , Biofilms , Archaea/physiology , Bacteria/metabolism , Ecosystem , Plants , Quorum Sensing
18.
Metab Brain Dis ; 37(3): 589-605, 2022 03.
Article in English | MEDLINE | ID: mdl-35102491

ABSTRACT

Hepatic encephalopathy (HE) is cerebral dysfunction caused by liver failure and inflicts 30-40% of patients with liver cirrhosis during their disease course. Clinically manifest HE is often preceded by minimal HE (MHE) - a clinically undetectable cognitive disturbance closely associated with loss of quality of life. Accordingly, detecting and treating MHE improve the patients' daily functioning and prevent HE-related hospital admissions. The scope of this review article is to create an overview of the validation level and usage of psychometric tests used to detect MHE: Portosystemic hepatic encephalopathy test, continuous reaction time test, Stroop EncephalApp, animal naming test, critical flicker frequency test, and inhibitory control test. Our work is aimed at the clinician or scientist who is about to decide on which psychometric test would fit best in their clinic, cohort, or study. First, we outline psychometric test validation obstacles and requirements. Then, we systematically approach the literature on each test and select well-conducted studies to answer the following questions:• Which percentage of patients with cirrhosis does the test deem as having MHE?• Is the test able to predict clinically manifest HE?• Is there a well-known test-retest variation and inter-observer variation?• Is the test able to detect a treatment response?• Is the test result affected by age, educational level, gender, or comorbidities?


Subject(s)
Cognitive Dysfunction , Hepatic Encephalopathy , Cognitive Dysfunction/complications , Humans , Liver Cirrhosis/complications , Liver Cirrhosis/diagnosis , Psychometrics/methods , Quality of Life
19.
Mol Ecol ; 31(5): 1595-1608, 2022 03.
Article in English | MEDLINE | ID: mdl-35014098

ABSTRACT

Horizontal gene transfer via plasmids is important for the dissemination of antibiotic resistance genes among medically relevant pathogens. Specifically, the transfer of IncHI1A plasmids is believed to facilitate the spread of antibiotic resistance genes, such as carbapenemases, within the clinically important family Enterobacteriaceae. The microbial community of urban wastewater treatment plants has been shown to be highly permissive towards conjugal transfer of IncP1 plasmids. Here, we tracked the transfer of the P1 plasmid pB10 and the clinically relevant HI1A plasmid R27 in the microbial communities present in urban residential sewage entering full-scale wastewater treatment plants. We found that both plasmids readily transferred to these communities and that strains in the sewage were able to further disseminate them. Furthermore, R27 has a broad potential host range, but a low host divergence. Interestingly, although the majority of R27 transfer events were to members of Enterobacteriaceae, we found a subset of transfer events to other families, even other phyla. This indicates that HI1A plasmids facilitate horizontal gene transfer both within Enterobacteriaceae, but also across families of, in particular, Gammaproteobacteria, such as Moraxellaceae, Pseudomonadaceae and Shewanellaceae. pB10 displayed a similar potential host range to R27. In contrast to R27, pB10 had a high host divergence. By culture enrichment of the transconjugant communities, we show that sewage strains of Enterobacteriaceae and Aeromonadaceae can stably maintain R27 and pB10, respectively. Our results suggest that dissemination in the urban residual water system of HI1A plasmids may result in an accelerated acquisition of antibiotic resistance genes among pathogens.


Subject(s)
Microbiota , Sewage , Anti-Bacterial Agents/pharmacology , Drug Resistance, Microbial/genetics , Gene Transfer, Horizontal/genetics , Plasmids/genetics , Sewage/microbiology
20.
Elife ; 102021 11 09.
Article in English | MEDLINE | ID: mdl-34751128

ABSTRACT

Bacteria commonly live in spatially structured biofilm assemblages, which are encased by an extracellular matrix. Metabolic activity of the cells inside biofilms causes gradients in local environmental conditions, which leads to the emergence of physiologically differentiated subpopulations. Information about the properties and spatial arrangement of such metabolic subpopulations, as well as their interaction strength and interaction length scales are lacking, even for model systems like Escherichia coli colony biofilms grown on agar-solidified media. Here, we use an unbiased approach, based on temporal and spatial transcriptome and metabolome data acquired during E. coli colony biofilm growth, to study the spatial organization of metabolism. We discovered that alanine displays a unique pattern among amino acids and that alanine metabolism is spatially and temporally heterogeneous. At the anoxic base of the colony, where carbon and nitrogen sources are abundant, cells secrete alanine via the transporter AlaE. In contrast, cells utilize alanine as a carbon and nitrogen source in the oxic nutrient-deprived region at the colony mid-height, via the enzymes DadA and DadX. This spatially structured alanine cross-feeding influences cellular viability and growth in the cross-feeding-dependent region, which shapes the overall colony morphology. More generally, our results on this precisely controllable biofilm model system demonstrate a remarkable spatiotemporal complexity of metabolism in biofilms. A better characterization of the spatiotemporal metabolic heterogeneities and dependencies is essential for understanding the physiology, architecture, and function of biofilms.


Subject(s)
Alanine/metabolism , Biofilms/growth & development , Escherichia coli/physiology , Metabolome , Transcriptome , Escherichia coli/growth & development , Spatial Analysis
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