RESUMEN
Adolescent cognitive and behavioral regulation is influenced by multidimensional and multidirectional processes within and across biological and contextual systems that shift throughout development. Key among these influences are distal processes such as early life socioeconomic position (SEP), and proximal processes such as pubertal development, but questions remain concerning how links between SEP, pubertal development, and cognitive and behavioral regulation accumulate and unfold over adolescence. In the current study, and in line with Dr. John Schulenberg's foundational work, direct associations between SEP, puberty, and adolescent cognitive and behavioral regulation were examined; then pubertal timing and tempo were considered as moderators and mediators of links between SEP and adolescent cognitive and behavioral regulation. Data were drawn from the NICHD Study of Early Child Care and Youth Development, a longitudinal study of 970 youth (52% male; 80% White, 13% Black, and 7% another race/ethnicity). Cognitive and behavioral regulation was measured using direct assessments of working memory, planning, risky decision-making, and impulse control at age 15. SEP included maternal education and family income-to-needs and was averaged from birth to 54 months old; estimates of pubertal timing and tempo were derived using logistic growth curve models from age 9 to age 15. SEP was directly associated with cognitive and behavioral regulation. Pubertal development tended to moderate those links, but rarely mediated them. Specifically, socioeconomic disadvantage along with earlier timing or faster tempo tended to be associated with worse cognitive and behavioral regulation. Overall, findings suggest that pubertal timing and tempo may exacerbate existing environmental constraints.
RESUMEN
Microbial transformation of bile acids affects intestinal immune homoeostasis but its impact on inflammatory pathologies remains largely unknown. Using a mouse model of graft-versus-host disease (GVHD), we found that T cell-driven inflammation decreased the abundance of microbiome-encoded bile salt hydrolase (BSH) genes and reduced the levels of unconjugated and microbe-derived bile acids. Several microbe-derived bile acids attenuated farnesoid X receptor (FXR) activation, suggesting that loss of these metabolites during inflammation may increase FXR activity and exacerbate the course of disease. Indeed, mortality increased with pharmacological activation of FXR and decreased with its genetic ablation in donor T cells during mouse GVHD. Furthermore, patients with GVHD after allogeneic hematopoietic cell transplantation showed similar loss of BSH and the associated reduction in unconjugated and microbe-derived bile acids. In addition, the FXR antagonist ursodeoxycholic acid reduced the proliferation of human T cells and was associated with a lower risk of GVHD-related mortality in patients. We propose that dysbiosis and loss of microbe-derived bile acids during inflammation may be an important mechanism to amplify T cell-mediated diseases.
Asunto(s)
Enfermedad Injerto contra Huésped , Linfocitos T , Humanos , Intestinos , Inflamación , Ácidos y Sales BiliaresRESUMEN
Colitis induced by treatment with immune-checkpoint inhibitors (ICI), termed irColitis, is a substantial cause of morbidity complicating cancer treatment. We hypothesized that abnormal fecal microbiome features would be present at the time of irColitis onset and that restoring the microbiome with fecal transplant from a healthy donor would mitigate disease severity. Herein, we present fecal microbiota profiles from 18 patients with irColitis from a single center, 5 of whom were treated with healthy-donor fecal microbial transplantation (FMT). Although fecal samples collected at onset of irColitis had comparable α-diversity to that of comparator groups with gastrointestinal symptoms, irColitis was characterized by fecal microbial dysbiosis. Abundances of Proteobacteria were associated with irColitis in multivariable analyses. Five patients with irColitis refractory to steroids and biologic anti-inflammatory agents received healthy-donor FMT, with initial clinical improvement in irColitis symptoms observed in four of five patients. Two subsequently exhibited recurrence of irColitis symptoms following courses of antibiotics. Both received a second "salvage" FMT that was, again, followed by clinical improvement of irColitis. In summary, we observed distinct microbial community changes that were present at the time of irColitis onset. FMT was followed by clinical improvements in several cases of steroid- and biologic-agent-refractory irColitis. Strategies to restore or prevent microbiome dysbiosis in the context of immunotherapy toxicities should be further explored in prospective clinical trials.
Asunto(s)
Productos Biológicos , Colitis , Microbioma Gastrointestinal , Humanos , Trasplante de Microbiota Fecal/efectos adversos , Estudios Prospectivos , Disbiosis/terapia , Disbiosis/etiología , Resultado del Tratamiento , Colitis/terapia , Colitis/complicacionesRESUMEN
T cells are the central drivers of many inflammatory diseases, but the repertoire of tissue-resident T cells at sites of pathology in human organs remains poorly understood. We examined the site-specificity of T cell receptor (TCR) repertoires across tissues (5 to 18 tissues per patient) in prospectively collected autopsies of patients with and without graft-versus-host disease (GVHD), a potentially lethal tissue-targeting complication of allogeneic hematopoietic cell transplantation, and in mouse models of GVHD. Anatomic similarity between tissues was a key determinant of TCR repertoire composition within patients, independent of disease or transplant status. The T cells recovered from peripheral blood and spleens in patients and mice captured a limited portion of the TCR repertoire detected in tissues. Whereas few T cell clones were shared across patients, motif-based clustering revealed shared repertoire signatures across patients in a tissue-specific fashion. T cells at disease sites had a tissue-resident phenotype and were of donor origin based on single-cell chimerism analysis. These data demonstrate the complex composition of T cell populations that persist in human tissues at the end stage of an inflammatory disorder after lymphocyte-directed therapy. These findings also underscore the importance of studying T cell in tissues rather than blood for tissue-based pathologies and suggest the tissue-specific nature of both the endogenous and posttransplant T cell landscape.
Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Humanos , Ratones , Animales , Linfocitos T/patología , Enfermedad Injerto contra Huésped/patología , Receptores de Antígenos de Linfocitos TRESUMEN
Discerning the effect of pharmacological exposures on intestinal bacterial communities in cancer patients is challenging. Here, we deconvoluted the relationship between drug exposures and changes in microbial composition by developing and applying a new computational method, PARADIGM (parameters associated with dynamics of gut microbiota), to a large set of longitudinal fecal microbiome profiles with detailed medication-administration records from patients undergoing allogeneic hematopoietic cell transplantation. We observed that several non-antibiotic drugs, including laxatives, antiemetics, and opioids, are associated with increased Enterococcus relative abundance and decreased alpha diversity. Shotgun metagenomic sequencing further demonstrated subspecies competition, leading to increased dominant-strain genetic convergence during allo-HCT that is significantly associated with antibiotic exposures. We integrated drug-microbiome associations to predict clinical outcomes in two validation cohorts on the basis of drug exposures alone, suggesting that this approach can generate biologically and clinically relevant insights into how pharmacological exposures can perturb or preserve microbiota composition. The application of a computational method called PARADIGM to a large dataset of cancer patients' longitudinal fecal specimens and detailed daily medication records reveals associations between drug exposures and the intestinal microbiota that recapitulate in vitro findings and are also predictive of clinical outcomes.
Asunto(s)
Microbioma Gastrointestinal , Trasplante de Células Madre Hematopoyéticas , Microbiota , Neoplasias , Humanos , Microbioma Gastrointestinal/genética , Heces/microbiología , Metagenoma , Antibacterianos , Neoplasias/tratamiento farmacológicoRESUMEN
Identifying predictive biomarkers of patient outcomes from high-throughput microbiome data is of high interest, while existing computational methods do not satisfactorily account for complex survival endpoints, longitudinal samples, and taxa-specific sequencing biases. We present FLORAL (https://vdblab.github.io/FLORAL/), an open-source computational tool to perform scalable log-ratio lasso regression and microbial feature selection for continuous, binary, time-to-event, and competing risk outcomes, with compatibility of longitudinal microbiome data as time-dependent covariates. The proposed method adapts the augmented Lagrangian algorithm for a zero-sum constraint optimization problem while enabling a two-stage screening process for extended false-positive control. In extensive simulation and real-data analyses, FLORAL achieved consistently better false-positive control compared to other lasso-based approaches, and better sensitivity over popular differential abundance testing methods for datasets with smaller sample size. In a survival analysis in allogeneic hematopoietic-cell transplant, we further demonstrated considerable improvement by FLORAL in microbial feature selection by utilizing longitudinal microbiome data over only using baseline microbiome data.
RESUMEN
Developmental cascades describe how systems of development interact and influence one another to shape human development across the lifespan. Despite its popularity, developmental cascades are commonly used to understand the developmental course of psychopathology, typically in the context of risk and resilience. Whether this framework can be useful for studying children's educational outcomes remains underexplored. Therefore, in this chapter, we provide an overview of how developmental cascades can be used to study children's academic development, with a particular focus on the biological, cognitive, and contextual pathways to educational attainment. We also provide a summary of contemporary statistical methods and highlight existing data sets that can be used to test developmental cascade models of educational attainment from birth through adulthood. We conclude the chapter by discussing the challenges of this research and explore important future directions of using developmental cascades to understand educational attainment.
Asunto(s)
Éxito Académico , Niño , Humanos , Escolaridad , Estudios LongitudinalesAsunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Humanos , Tracto Gastrointestinal , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/prevención & control , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Anticuerpos Monoclonales Humanizados/uso terapéuticoRESUMEN
PURPOSE: The gut microbiota is subject to multiple insults in allogeneic hematopoietic cell transplantation (allo-HCT) recipients. We hypothesized that preparative conditioning regimens contribute to microbiota perturbation in allo-HCT. EXPERIMENTAL DESIGN: This was a retrospective study that evaluated the relationship between conditioning regimens exposure in 1,188 allo-HCT recipients and the gut microbiome. Stool samples collected from 20 days before transplantation up to 30 days after were profiled using 16S rRNA sequencing. Microbiota injury was quantified by changes in α-diversity. RESULTS: We identified distinct patterns of microbiota injury that varied by conditioning regimen. Diversity loss was graded into three levels of conditioning-associated microbiota injury (CMBI) in a multivariable model that included antibiotic exposures. High-intensity regimens, such as total body irradiation (TBI)-thiotepa-cyclophosphamide, were associated with the greatest injury (CMBI III). In contrast, the nonmyeloablative regimen fludarabine-cyclophosphamide with low-dose TBI (Flu/Cy/TBI200) had a low-grade injury (CMBI I). The risk of acute GVHD correlated with CMBI degree. Pretransplant microbial compositions were best preserved with Flu/Cy/TBI200, whereas other regimens were associated with loss of commensal bacteria and expansion of Enterococcus. CONCLUSIONS: Our findings support an interaction between conditioning at the regimen level and the extent of microbiota injury.
Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Microbiota , Humanos , Estudios Retrospectivos , ARN Ribosómico 16S , Trasplante Homólogo/efectos adversos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Ciclofosfamida/efectos adversos , Enfermedad Injerto contra Huésped/diagnóstico , Enfermedad Injerto contra Huésped/etiología , Acondicionamiento Pretrasplante/efectos adversosRESUMEN
Hospitalized patients receiving hematopoietic cell transplants provide a unique opportunity to study the human gut microbiome. We previously compiled a large-scale longitudinal dataset of fecal microbiota and associated metadata, but we had limited that analysis to taxonomic composition of bacteria from 16S rRNA gene sequencing. Here we augment those data with shotgun metagenomics. The compilation amounts to a nested subset of 395 samples compiled from different studies at Memorial Sloan Kettering. Shotgun metagenomics describes the microbiome at the functional level, particularly in antimicrobial resistances and virulence factors. We provide accession numbers that link each sample to the paired-end sequencing files deposited in a public repository, which can be directly accessed by the online services of PATRIC to be analyzed without the users having to download or transfer the files. Then, we show how shotgun sequencing enables the assembly of genomes from metagenomic data. The new data, combined with the metadata published previously, enables new functional studies of the microbiomes of patients with cancer receiving bone marrow transplantation.
Asunto(s)
Heces , Trasplante de Células Madre Hematopoyéticas , Microbiota , Heces/microbiología , Humanos , Metagenómica , Microbiota/genética , ARN Ribosómico 16S/genéticaRESUMEN
The AMP-activated protein kinase (AMPK) αßγ heterotrimer is a primary cellular energy sensor and central regulator of energy homeostasis. Activating skeletal muscle AMPK with small molecule drugs improves glucose uptake and provides an opportunity for new strategies to treat type 2 diabetes and insulin resistance, with recent genetic and pharmacological studies indicating the α2ß2γ1 isoform combination as the heterotrimer complex primarily responsible. With the goal of developing α2ß2-specific activators, here we perform structure/function analysis of the 2-hydroxybiphenyl group of SC4, an activator with tendency for α2-selectivity that is also capable of potently activating ß2 complexes. Substitution of the LHS 2-hydroxyphenyl group with polar-substituted cyclohexene-based probes resulted in two AMPK agonists, MSG010 and MSG011, which did not display α2-selectivity when screened against a panel of AMPK complexes. By radiolabel kinase assay, MSG010 and MSG011 activated α2ß2γ1 AMPK with one order of magnitude greater potency than the pan AMPK activator MK-8722. A crystal structure of MSG011 complexed to AMPK α2ß1γ1 revealed a similar binding mode to SC4 and the potential importance of an interaction between the SC4 2-hydroxyl group and α2-Lys31 for directing α2-selectivity. MSG011 induced robust AMPK signalling in mouse primary hepatocytes and commonly used cell lines, and in most cases this occurred in the absence of changes in phosphorylation of the kinase activation loop residue α-Thr172, a classical marker of AMP-induced AMPK activity. These findings will guide future design of α2ß2-selective AMPK activators, that we hypothesise may avoid off-target complications associated with indiscriminate activation of AMPK throughout the body.
Asunto(s)
Proteínas Quinasas Activadas por AMP , Diabetes Mellitus Tipo 2 , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Línea Celular , Diabetes Mellitus Tipo 2/metabolismo , Ratones , Músculo Esquelético/metabolismo , FosforilaciónRESUMEN
Low intestinal microbial diversity is associated with poor outcomes after allogeneic hematopoietic cell transplantation (HCT). Using 16S rRNA sequencing of 2067 stool samples and flow cytometry data from 2370 peripheral blood samples drawn from 894 patients who underwent allogeneic HCT, we have linked features of the early post-HCT microbiome with subsequent immune cell recovery. We examined lymphocyte recovery and microbiota features in recipients of both unmodified and CD34-selected allografts. We observed that fecal microbial diversity was an independent predictor of CD4 T-cell count 3 months after HCT in recipients of a CD34-selected allograft, who are dependent on de novo lymphopoiesis for their immune recovery. In multivariate models using clinical factors and microbiota features, we consistently observed that increased fecal relative abundance of genus Staphylococcus during the early posttransplant period was associated with worse CD4 T-cell recovery. Our observations suggest that the intestinal bacteria, or the factors they produce, can affect early lymphopoiesis and the homeostasis of allograft-derived T cells after transplantation.
Asunto(s)
Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Linfocitos T CD4-Positivos , Humanos , Recuento de Linfocitos , ARN Ribosómico 16S , Trasplante HomólogoRESUMEN
Pirepemat (IRL752) is a cortical enhancer being developed for the prevention of falls in patients with Parkinson disease. This first-in-human, randomized, double-blind, placebo-controlled phase 1 study evaluated safety, tolerability, and pharmacokinetics (PK) of pirepemat administered as oral single ascending doses (10, 35, 75, 175, 350 mg) and multiple ascending doses (100 and 250 mg 3 times daily) for 7 days to healthy male volunteers. Twenty and 24 subjects were randomly assigned in the single ascending dose and multiple ascending doses parts of the study, respectively. Pirepemat was generally well tolerated, although an increased frequency of adverse events of mild intensity within nervous system disorders (headache and dizziness) was seen after administration of 350 mg as a single dose and after multiple doses of 100 and 250 mg. PK of pirepemat showed a linear relationship over the dose range studied and exhibited dose proportionality after multiple-dose administration. Accumulation after 7 days of multiple dosing was minor. Absorption was rapid, with a median time to maximum concentration of 2.0 hours on day 1 and day 7 (100 and 250 mg) and a mean terminal half-life between 3.7 and 5.2 hours. Food intake had no (obvious) impact on PK. The results support 3-times-daily dosing and further clinical development.
Asunto(s)
Voluntarios Sanos , Área Bajo la Curva , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Humanos , MasculinoRESUMEN
The management of Parkinson's disease (PD) is frequently compromised by complications induced by dopaminergic treatment such as involuntary movements (dyskinesias) and psychosis. Mesdopetam (IRL790) is a novel dopamine D3 receptor antagonist developed for the management of complications of therapy in PD. This study evaluated the safety, tolerability, and pharmacokinetics of escalating single and multiple doses of mesdopetam. We conducted a prospective, single-center, randomized, double-blind, placebo-controlled phase I, and first-in-human (FIH) study with mesdopetam administered to healthy male subjects. Overall, mesdopetam was well-tolerated up to a 120 mg single dose and up to 80 mg upon multiple dosing. Adverse events (AEs) were mainly related to the nervous system and were dose-dependent. No serious adverse events occurred and no AEs led to withdrawal. The results of the single-ascending-dose and multiple-ascending-dose parts indicated dose- and time-independent pharmacokinetics with rapid absorption and maximum plasma levels that were generally reached within 2 h after dosing. No accumulation was observed upon multiple dosing. It is concluded that mesdopetam was safe and well-tolerated in healthy male volunteers. Pharmacokinetic analysis indicated rapid absorption and dose-linear pharmacokinetics of mesdopetam, with a plasma half-life of around 7 h, upon single and repeated dosing. The pharmacokinetics of mesdopetam supports twice-daily use in patients.
Asunto(s)
Antagonistas de Dopamina/administración & dosificación , Éteres Fenílicos/administración & dosificación , Propilaminas/administración & dosificación , Receptores de Dopamina D3/antagonistas & inhibidores , Administración Oral , Adolescente , Adulto , Disponibilidad Biológica , Antagonistas de Dopamina/efectos adversos , Antagonistas de Dopamina/farmacocinética , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Ayuno/metabolismo , Interacciones Alimento-Droga , Semivida , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Éteres Fenílicos/efectos adversos , Éteres Fenílicos/farmacocinética , Propilaminas/efectos adversos , Propilaminas/farmacocinética , Adulto JovenRESUMEN
Among the many factors contributing to the SES-achievement gap, executive function (EF) skills have received a considerable amount of attention, given their role in supporting academic skill development. While recent work has demonstrated that global EF constructs mediate SES-achievement relations, less attention has been paid to unpacking the role of specific EF components in linking SES to achievement. Data from the NICHD Study of Early Child Care and Youth Development (N = 1,273) were analyzed to assess direct and indirect associations between SES indicators, preschool EF skills, and first-grade math and reading achievement. Using path analysis, we found parent education and working memory to be uniquely and most predictive of both achievement domains. Further, after controlling for baseline academic skills, verbal ability, and other child- and family-level covariates, only working memory mediated the association between parent education and children's math achievement. These findings offer a comprehensive look at the specific mechanisms through which socioeconomic disadvantage contributes to children's academic development and provide an initial step towards generating more precise targets for policies and interventions aimed at closing the achievement gap.
RESUMEN
The Clermont PCR method for phylotyping Escherichia coli remains a useful classification scheme even though genome sequencing is now routine, and higher-resolution sequence typing schemes are now available. Relating present-day whole-genome E. coli classifications to legacy phylotyping is essential for harmonizing the historical literature and understanding of this important organism. Therefore, we present EzClermont - a novel in silico Clermont PCR phylotyping tool to enable ready application of this phylotyping scheme to whole-genome assemblies. We evaluate this tool against phylogenomic classifications, and an alternative software implementation of Clermont typing. EzClermont is available as a web app at www.ezclermont.org, and as a command-line tool at https://nickp60.github.io/EzClermont/.
RESUMEN
Chronic lung infection with bacterial biofilms is a leading cause of death in cystic fibrosis (CF) patients. Pseudomonas aeruginosa, one of the many species colonizing the lung airways, can undergo pathoadaptation, leading to a mucoid phenotype with interesting material properties. We hypothesize that the surface properties and extracellular materials of mucoid P. aeruginosa cells greatly influence the mechanical behavior of their films at fluid interfaces. In this study, we investigate the interfacial properties of films formed by nonmucoid (PANT) and mucoid (PASL) strains of P. aeruginosa isolated from CF patients. We use pendant drop elastometry to analyze the interfacial response of the films formed by PANT and PASL at the hexadecane-water interface. The dynamic rheological analyses of the films highlight the distinctive signature of the mucoid strains at fluid interfaces. The mucoid films exhibit greater relaxation following a compressive strain than a tensile one, while a full hysteresis response is achieved by the nonmucoid films; this indicates that the material properties of the PANT films are conserved under both compression and tension. The wrinkling and shape analyses of the interfacial bacterial films elucidate that the mucoid strain exhibits remarkable viscoelastic properties, enabling the remodeling of the living films and dissipation of the compressive stress. The comparative analysis of the material properties of mucoid and nonmucoid P. aeruginosa cells indicates that mucoid switch can play an important role in protecting the bacteria from interfacial stresses. Further characterization of interfacial bacterial films will provide new insights into the development of methods for controlling interfacial films of bacteria.
Asunto(s)
Fibrosis Quística , Infecciones por Pseudomonas , Biopelículas , Humanos , Pulmón , Pseudomonas aeruginosaRESUMEN
IRL790 ([2-(3-fluoro-5-methanesulfonylphenoxy)ethyl](propyl)amine, mesdopetam) is a novel compound in development for the clinical management of motor and psychiatric disabilities in Parkinson disease. The discovery of IRL790 was made applying a systems pharmacology approach based on in vivo response profiling. The chemical design idea was to develop a new type of DA D3/D2 receptor type antagonist built on agonist rather than antagonist structural motifs. We hypothesized that such a dopamine antagonist with physicochemical properties similar to agonists would exert antidyskinetic and antipsychotic effects in states of dysregulated dopaminergic signaling while having little negative impact on physiologic dopamine transmission and, hence, minimal liability for side effects related to dopamine-dependent functions. At the level of in vivo pharmacology, IRL790 displays balancing effects on aberrant motor phenotypes, reducing l-DOPA-induced dyskinesias in the rodent 6-hydroxydopamine lesion model and reducing psychostimulant-induced locomotor hyperactivity elicited by pretreatment with either d-amphetamine or dizocilpine, without negatively impacting normal motor performance. Thus, IRL790 has the ability to normalize the behavioral phenotype in hyperdopaminergic as well as hypoglutamatergic states. Neurochemical and immediate early gene (IEG) response profiles suggest modulation of DA neurotransmission, with some features, such as increased DA metabolites and extracellular DA, shared by atypical antipsychotics and others, such as increased frontal cortex IEGs, unique to IRL790. IRL790 also increases extracellular levels of acetylcholine in the prefrontal cortex and ventral hippocampus. At the receptor level, IRL790 appears to act as a preferential DA D3 receptor antagonist. Computational docking studies support preferential affinity at D3 receptors with an agonist-like binding mode. SIGNIFICANCE STATEMENT: This paper reports preclinical pharmacology along with molecular modeling results on IRL790, a novel compound in clinical development for the treatment of motor and psychiatric complications in advanced Parkinson disease. IRL790 is active in models of perturbed dopaminergic and glutamatergic signaling, including rodent 6-hydroxydopamine l-DOPA-induced dyskinesias and psychostimulant-induced hyperactivity, in a dose range that does not impair normal behavior. This effect profile is attributed to interactions at dopamine D2/D3 receptors, with a 6- to 8-fold preference for the D3 subtype.
Asunto(s)
Dopamina/metabolismo , Trastornos Mentales/complicaciones , Trastornos Motores/complicaciones , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Animales , Conducta Animal/efectos de los fármacos , Masculino , Simulación del Acoplamiento Molecular , Enfermedad de Parkinson/complicaciones , Conformación Proteica , Ratas , Ratas Sprague-Dawley , Receptores de Dopamina D3/química , Receptores de Dopamina D3/metabolismoRESUMEN
SUMMARY: The overarching aim of microbiome analysis is to uncover the links between microbial phylogeny and function in order to access ecosystem functioning. This can be done using several experimental strategies targeting different biomolecules, including DNA (metagenomics), RNA (metatranscriptomics) and proteins (metaproteomics). Despite the importance of linking microbial function to phylogeny there are currently no visualization tools that effectively integrate this information. Chordomics is a Shiny-based application for linked -omics data analysis, allowing users to visualize microbial function and phylogeny on a single plot and compare datasets across time and environments. AVAILABILITY AND IMPLEMENTATION: Chordomics is available on GitHub: https://github.com/kevinmcdonnell6/chordomics; software is coded in R and JavaScript and a demonstration version is available at https://kmcd.shinyapps.io/ChordomicsDemo/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
Asunto(s)
Microbiota , Programas Informáticos , Metagenómica , FilogeniaRESUMEN
Inorganic polyphosphate (polyP) is ubiquitous across all forms of life, but the study of its metabolism has been mainly confined to bacteria and yeasts. Few reports detail the presence and accumulation of polyP in Archaea, and little information is available on its functions and regulation. Here, we report that homologs of bacterial polyP metabolism proteins are present across the major taxa in the Archaea, suggesting that archaeal populations may have a greater contribution to global phosphorus cycling than has previously been recognised. We also demonstrate that polyP accumulation can be induced under strictly anaerobic conditions, in response to changes in phosphate (Pi) availability, i.e. Pi starvation, followed by incubation in Pi replete media (overplus), in cells of the methanogenic archaeon Methanosarcina mazei. Pi-starved M. mazei cells increased transcript abundance of the alkaline phosphatase (phoA) gene and of the high-affinity phosphate transport (pstSCAB-phoU) operon: no increase in polyphosphate kinase 1 (ppk1) transcript abundance was observed. Subsequent incubation of Pi-starved M. mazei cells under Pi replete conditions, led to a 237% increase in intracellular polyphosphate content and a > 5.7-fold increase in ppk1 gene transcripts. Ppk1 expression in M. mazei thus appears not to be under classical phosphate starvation control.