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1.
Blood Adv ; 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39133891

RESUMO

Infants with B-cell acute lymphoblastic leukemia (B-ALL) continue to have significantly worse outcomes compared to older children with B-ALL, and those with relapsed or refractory (R/R) infant ALL have especially dismal outcomes with conventional treatment. CD19-targeting chimeric antigen receptor (CAR) T-cell therapy has demonstrated remarkable success in the treatment of R/R childhood B-ALL, though the majority of reports have been in non-infant patients. Barriers to the successful implementation of CAR T-cell therapy in infant B-ALL include challenges related to apheresis, product manufacturing and disease-specific considerations such as lineage switch. We describe our experience utilizing two experimental CD19-CAR T-cell products, SCRI-CAR19 or SCRI-CAR19x22, for 19 patients with R/R infant B-ALL enrolled on three clinical trials. CAR T-cell products were successfully manufactured in 18/19 (94.7%) patients, with a median age of 22.5 months at enrollment (range, 14.5-40.1 months). Sixteen of 17 (94.1%) treated patients achieved a complete remission without detectable minimal residual disease. The 1-year leukemia free survival was 75% and 1-year overall survival was 76.5%, with a median follow up time of 35.8 months (range, 1.7-83.6 months). Cytokine release syndrome (CRS) occurred in 14/17 (82.4%) patients, with only 1 patient experiencing Grade 3 CRS. Neurotoxicity occurred in 2/17 (11.8%) patients with all events ≤ Grade 2. With the successful early clinical experience of CAR T-cell therapy in this population, more systematic evaluation specific to infant ALL is warranted.

2.
Nucleic Acids Res ; 52(D1): D590-D596, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37889041

RESUMO

CRISPR-Cas enzymes enable RNA-guided bacterial immunity and are widely used for biotechnological applications including genome editing. In particular, the Class 2 CRISPR-associated enzymes (Cas9, Cas12 and Cas13 families), have been deployed for numerous research, clinical and agricultural applications. However, the immense genetic and biochemical diversity of these proteins in the public domain poses a barrier for researchers seeking to leverage their activities. We present CasPEDIA (http://caspedia.org), the Cas Protein Effector Database of Information and Assessment, a curated encyclopedia that integrates enzymatic classification for hundreds of different Cas enzymes across 27 phylogenetic groups spanning the Cas9, Cas12 and Cas13 families, as well as evolutionarily related IscB and TnpB proteins. All enzymes in CasPEDIA were annotated with a standard workflow based on their primary nuclease activity, target requirements and guide-RNA design constraints. Our functional classification scheme, CasID, is described alongside current phylogenetic classification, allowing users to search related orthologs by enzymatic function and sequence similarity. CasPEDIA is a comprehensive data portal that summarizes and contextualizes enzymatic properties of widely used Cas enzymes, equipping users with valuable resources to foster biotechnological development. CasPEDIA complements phylogenetic Cas nomenclature and enables researchers to leverage the multi-faceted nucleic-acid targeting rules of diverse Class 2 Cas enzymes.


Assuntos
Proteínas Associadas a CRISPR , Sistemas CRISPR-Cas , Bases de Dados Genéticas , Endodesoxirribonucleases , Sistemas CRISPR-Cas/genética , Filogenia , Proteínas Associadas a CRISPR/química , Proteínas Associadas a CRISPR/classificação , Proteínas Associadas a CRISPR/genética , Endodesoxirribonucleases/química , Endodesoxirribonucleases/classificação , Endodesoxirribonucleases/genética , Enciclopédias como Assunto
3.
CRISPR J ; 6(3): 261-277, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37272861

RESUMO

Type II Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-Cas9 nucleases have been extensively used in biotechnology and therapeutics. However, many applications are not possible owing to the size, targetability, and potential off-target effects associated with currently known systems. In this study, we identified thousands of CRISPR type II effectors by mining an extensive, genome-resolved metagenomics database encompassing hundreds of thousands of microbial genomes. We developed a high-throughput pipeline that enabled us to predict tracrRNA sequences, to design single guide RNAs, and to demonstrate nuclease activity in vitro for 41 newly described subgroups. Active systems represent an extensive diversity of protein sequences and guide RNA structures and require diverse protospacer adjacent motifs (PAMs) that collectively expand the known targeting capability of current systems. Several nucleases showed activity levels comparable to or significantly higher than SpCas9, despite being smaller in size. In addition, top systems exhibited low levels of off-target editing in mammalian cells, and PAM-interacting domain engineered chimeras further expanded their targetability. These newly discovered nucleases are attractive enzymes for translation into many applications, including therapeutics.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Animais , Sistemas CRISPR-Cas/genética , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Biotecnologia , RNA Guia de Sistemas CRISPR-Cas , Mamíferos/genética , Mamíferos/metabolismo
4.
CRISPR J ; 6(3): 243-260, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37219969

RESUMO

Development of medicines using gene editing has been hampered by enzymological and immunological impediments. We described previously the discovery and characterization of improved, novel gene-editing systems from metagenomic data. In this study, we substantially advance this work with three such gene-editing systems, demonstrating their utility for cell therapy development. All three systems are capable of reproducible, high-frequency gene editing in primary immune cells. In human T cells, disruption of the T cell receptor (TCR) alpha-chain was induced in >95% of cells, both paralogs of the TCR beta-chain in >90% of cells, and >90% knockout of ß2-microglobulin, TIGIT, FAS, and PDCD1. Simultaneous double knockout of TRAC and TRBC was obtained at a frequency equal to that of the single edits. Gene editing with our systems had minimal effect on T cell viability. Furthermore, we integrate a chimeric antigen receptor (CAR) construct into TRAC (up to ∼60% of T cells), and demonstrate CAR expression and cytotoxicity. We next applied our novel gene-editing tools to natural killer (NK) cells, B cells, hematopoietic stem cells, and induced pluripotent stem cells, generating similarly efficient cell-engineering outcomes including the creation of active CAR-NK cells. Interrogation of our gene-editing systems' specificity reveals a profile comparable with or better than Cas9. Finally, our nucleases lack preexisting humoral and T cell-based immunity, consistent with their sourcing from nonhuman pathogens. In all, we show these new gene-editing systems have the activity, specificity, and translatability necessary for use in cell therapy development.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Humanos , Sistemas CRISPR-Cas/genética , Linfócitos T/metabolismo , Diferenciação Celular , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo
5.
Appl Environ Microbiol ; 89(5): e0002523, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37098974

RESUMO

The Candidate Phyla Radiation (CPR), also referred to as superphylum Patescibacteria, is a very large group of bacteria with no pure culture representatives discovered by 16S rRNA sequencing or genome-resolved metagenomic analyses of environmental samples. Within the CPR, candidate phylum Parcubacteria, previously referred to as OD1, is prevalent in anoxic sediments and groundwater. Previously, we had identified a specific member of the Parcubacteria (referred to as DGGOD1a) as an important member of a methanogenic benzene-degrading consortium. Phylogenetic analyses herein place DGGOD1a within the clade "Candidatus Nealsonbacteria." Because of its persistence over many years, we hypothesized that "Ca. Nealsonbacteria" DGGOD1a must play an important role in sustaining anaerobic benzene metabolism in the consortium. To try to identify its growth substrate, we amended the culture with a variety of defined compounds (pyruvate, acetate, hydrogen, DNA, and phospholipid), as well as crude culture lysate and three subfractions thereof. We observed the greatest (10-fold) increase in the absolute abundance of "Ca. Nealsonbacteria" DGGOD1a only when the consortium was amended with crude cell lysate. These results implicate "Ca. Nealsonbacteria" in biomass recycling. Fluorescence in situ hybridization and cryogenic transmission electron microscope images revealed that "Ca. Nealsonbacteria" DGGOD1a cells were attached to larger archaeal Methanothrix cells. This apparent epibiont lifestyle was supported by metabolic predictions from a manually curated complete genome. This is one of the first examples of bacterial-archaeal episymbiosis and may be a feature of other "Ca. Nealsonbacteria" found in anoxic environments. IMPORTANCE An anaerobic microbial enrichment culture was used to study members of candidate phyla that are difficult to grow in the lab. We were able to visualize tiny "Candidatus Nealsonbacteria" cells attached to a large Methanothrix cell, revealing a novel episymbiosis.


Assuntos
Archaea , Euryarchaeota , Archaea/metabolismo , Benzeno/metabolismo , Filogenia , Biomassa , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Hibridização in Situ Fluorescente , Bactérias/genética , Euryarchaeota/metabolismo
6.
Nat Commun ; 13(1): 7602, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36522342

RESUMO

Programmable, RNA-guided nucleases are diverse enzymes that have been repurposed for biotechnological applications. However, to further expand the therapeutic application of these tools there is a need for targetable systems that are small enough to be delivered efficiently. Here, we mined an extensive genome-resolved metagenomics database and identified families of uncharacterized RNA-guided, compact nucleases (between 450 and 1,050 aa). We report that Cas9d, a new CRISPR type II subtype, contains Zinc-finger motifs and high arginine content, features that we also found in nucleases related to HEARO effectors. These enzymes exhibit diverse biochemical characteristics and are broadly targetable. We show that natural Cas9d enzymes are capable of genome editing in mammalian cells with >90% efficiency, and further engineered nickase variants into the smallest base editors active in E. coli and human cells. Their small size, broad targeting potential, and translatability suggest that Cas9d and HEARO systems will enable a variety of genome editing applications.


Assuntos
Escherichia coli , Edição de Genes , Animais , Humanos , Escherichia coli/genética , Escherichia coli/metabolismo , Endonucleases/genética , Endonucleases/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Ribonucleases/genética , RNA , Sistemas CRISPR-Cas/genética , Mamíferos/genética
7.
Phys Chem Chem Phys ; 24(27): 16891-16899, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35788234

RESUMO

Organic radical emitters have received significant attention as a new route to efficient organic light-emitting diodes (OLEDs). The electronic structure of radical emitters allows bypassing the triplet harvesting issue in current OLED devices. However, the nature of doublet excited states remains elusive due to the complex nature of emissive layers. To date, the computational efforts have treated radical carrying materials as isolated entities in the gas phase. However, OLED materials are applied as thin solid films where intermolecular interactions significantly impact optoelectronic properties of the devices. Here, we combine molecular dynamics simulations and quantum chemical calculations to evaluate the effect of emitter-host interactions on the performance of radical-based emissive layers. Results demonstrate that intermolecular interactions remarkably modulate the electronic properties of the radicals in the thin solid films. The doublet excitons of isolated emitters demonstrate a hybrid character of charge-transfer (CT) and local-excitation (LE), while the emitter-host clusters present a significant CT character. Further, the impact of static and dynamic disorders on the hole-electron recombination is studied. Although the host-emitter interactions simultaneously decrease radiative rates and increase non-radiative rates, the latter rates are 100 times smaller than the former rates, allowing internal quantum efficiency to reach 100% for the doublet-based emission process. The results of this study highlight the significant impact of host-emitter interactions on radiative and non-radiative recombination processes and offer guidelines to tune these interactions for advancing radical-based OLEDs.

8.
J Bone Joint Surg Am ; 103(16): e64, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-33950879

RESUMO

BACKGROUND: Supraphysiologic bone morphogenetic protein (BMP)-2 concentrations are required to induce spinal fusion. In this study, a BMP-2/BMP-6/activin A chimera (BV-265), optimized for BMP receptor binding, delivered in a recombinant human collagen:CDHA [calcium-deficient hydroxyapatite] porous composite matrix (CM) or bovine collagen:CDHA granule porous composite matrix (PCM), engineered for optimal BV-265 retention and guided tissue repair, was compared with BMP-2 delivered in a bovine absorbable collagen sponge (ACS) wrapped around a MASTERGRAFT Matrix (MM) ceramic-collagen rod (ACS:MM) in a nonhuman primate noninstrumented posterolateral fusion (PLF) model. METHODS: In vivo retention of 125I-labeled-BV-265/CM or PCM was compared with 125I-labeled-BMP-2/ACS or BMP-2/buffer in a rat muscle pouch model using scintigraphy. Noninstrumented PLF was performed by implanting CM, BV-265/CM, BV-265/PCM, or BMP-2/ACS:MM across L3-L4 and L5-L6 or L3-L4-L5 decorticated transverse processes in 26 monkeys. Computed tomography (CT) images were acquired at 0, 4, 8, 12, and 24 weeks after surgery, where applicable. Manual palpation, µCT (microcomputed tomography) or nCT (nanocomputed tomography), and histological analysis were performed following euthanasia. RESULTS: Retention of 125I-labeled-BV-265/CM was greater than BV-265/PCM, followed by BMP-2/ACS and BMP-2/buffer. The CM, 0.43 mg/cm3 BMP-2/ACS:MM, and 0.05 mg/cm3 BV-265/CM failed to generate PLFs. The 0.15-mg/cm3 BV-265/CM or 0.075-mg/cm3 BV-265/PCM combinations were partially effective. The 0.25-mg/cm3 BV-265/CM and 0.15 and 0.3-mg/cm3 BV-265/PCM combinations generated successful 2-level PLFs at 12 and 24 weeks. CONCLUSIONS: BV-265/CM or PCM can induce fusion in a challenging nonhuman primate noninstrumented PLF model at substantially lower concentrations than BMP-2/ACS:MM. CLINICAL RELEVANCE: BV-265/CM and PCM represent potential alternatives to induce PLF in humans at substantially lower concentrations than BMP-2/ACS:MM.


Assuntos
Proteínas Recombinantes de Fusão/administração & dosagem , Doenças da Coluna Vertebral/terapia , Fusão Vertebral/métodos , Ativinas/genética , Animais , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 6/genética , Relação Dose-Resposta a Droga , Humanos , Radioisótopos do Iodo/química , Macaca mulatta , Masculino , Modelos Animais , Ratos , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética
9.
Front Chem ; 9: 800370, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35111730

RESUMO

In recent years, generative machine learning approaches have attracted significant attention as an enabling approach for designing novel molecular materials with minimal design bias and thereby realizing more directed design for a specific materials property space. Further, data-driven approaches have emerged as a new tool to accelerate the development of novel organic electronic materials for organic light-emitting diode (OLED) applications. We demonstrate and validate a goal-directed generative machine learning framework based on a recurrent neural network (RNN) deep reinforcement learning approach for the design of hole transporting OLED materials. These large-scale molecular simulations also demonstrate a rapid, cost-effective method to identify new materials in OLEDs while also enabling expansion into many other verticals such as catalyst design, aerospace, life science, and petrochemicals.

10.
CRISPR J ; 3(6): 454-461, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33146573

RESUMO

Cas12a enzymes are quickly being adopted for use in a variety of genome-editing applications. These programmable nucleases are part of adaptive microbial immune systems, the natural diversity of which has been largely unexplored. Here, we identified novel families of Type V-A CRISPR nucleases through a large-scale analysis of metagenomes collected from a variety of complex environments, and developed representatives of these systems into gene-editing platforms. The nucleases display extensive protein variation and can be programmed by a single-guide RNA with specific motifs. The majority of these enzymes are part of systems recovered from uncultivated organisms, some of which also encode a divergent Type V effector. Biochemical analysis uncovered unexpected protospacer adjacent motif diversity, indicating that these systems will facilitate a variety of genome-engineering applications. The simplicity of guide sequences and activity in human cell lines suggest utility in gene and cell therapies.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Proteínas Associadas a CRISPR/isolamento & purificação , Proteínas Associadas a CRISPR/metabolismo , Endodesoxirribonucleases/isolamento & purificação , Endodesoxirribonucleases/metabolismo , Edição de Genes/métodos , Bactérias/genética , Proteínas de Bactérias/genética , Proteína 9 Associada à CRISPR/genética , Proteínas Associadas a CRISPR/genética , Sistemas CRISPR-Cas/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Endodesoxirribonucleases/genética , Endonucleases/genética , Edição de Genes/tendências , Humanos , Metagenômica/métodos , Filogenia , RNA Guia de Cinetoplastídeos/genética
11.
J Pediatr Urol ; 16(3): 390-391, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32336598

RESUMO

We describe a fast and easy puncture technique of prolapsed ureteroceles at the bedside without anesthesia or sedation.


Assuntos
Anestesia , Ureterocele , Humanos , Punções , Ureterocele/diagnóstico por imagem , Ureterocele/cirurgia
12.
PLoS One ; 15(3): e0229537, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130257

RESUMO

Microbes alter their transcriptomic profiles in response to the environment. The physiological conditions experienced by a microbial community can thus be inferred using meta-transcriptomic sequencing by comparing transcription levels of specifically chosen genes. However, this analysis requires accurate reference genomes to identify the specific genes from which RNA reads originate. In addition, such an analysis should avoid biases in transcript counts related to differences in organism abundance. In this study we describe an approach to address these difficulties. Sample-specific meta-genomic assembled genomes (MAGs) were used as reference genomes to accurately identify the origin of RNA reads, and transcript ratios of genes with opposite transcription responses were compared to eliminate biases related to differences in organismal abundance, an approach hereafter named the "diametric ratio" method. We used this approach to probe the environmental conditions experienced by Escherichia spp. in the gut of 4 premature infants, 2 of whom developed necrotizing enterocolitis (NEC), a severe inflammatory intestinal disease. We analyzed twenty fecal samples taken from four premature infants (4-6 time points from each infant), and found significantly higher diametric ratios of genes associated with low oxygen levels in samples of infants later diagnosed with NEC than in samples without NEC. We also show this method can be used for examining other physiological conditions, such as exposure to nitric oxide and osmotic pressure. These study results should be treated with caution, due to the presence of confounding factors that might also distinguish between NEC and control infants. Nevertheless, together with benchmarking analyses, we show here that the diametric ratio approach can be applied for evaluating the physiological conditions experienced by microbes in situ. Results from similar studies can be further applied for designing diagnostic methods to detect NEC in its early developmental stages.


Assuntos
Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiologia , Recém-Nascido Prematuro/fisiologia , Estudos de Casos e Controles , Bases de Dados Genéticas , Sistema Digestório/microbiologia , Fenômenos Fisiológicos do Sistema Digestório , Complexo IV da Cadeia de Transporte de Elétrons/genética , Enterocolite Necrosante/diagnóstico , Enterocolite Necrosante/genética , Enterocolite Necrosante/microbiologia , Escherichia/genética , Escherichia/isolamento & purificação , Feminino , Genes Bacterianos , Humanos , Recém-Nascido , Masculino , Metagenoma , Microbiota/genética , Transcriptoma
13.
J Robot Surg ; 14(6): 865-870, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32200542

RESUMO

The objective of this study is to determine recent trends in use of robotics and laparoscopy for pediatric retroperitoneal lymph-node dissection (RPLND) in pediatric and non-pediatric hospitals. We conducted a retrospective cohort study using data from 29 hospitals in the Pediatric Health Information System (PHIS), and data from 14 states in the State Inpatient Databases (SID), between 2008 and 2014. The study population was comprised of patients aged ≥ 10 years undergoing RPLND, with an inpatient diagnosis of testicular or paratesticular cancer, based on international classification of disease (ICD) codes. Robotic approach was identified by the presence of an ICD procedure code modifier. During the study period, a total of 90 RPLNDs were performed in pediatric hospitals (median patient age 16 years). Of these, 4 (4.4%) were performed robotically. A total of 3120 RPLNDs were performed in non-pediatric hospitals (median patient age: 32 years). Among these, 269 (8.6%) were performed robotically, with an increasing trend in the use of robotic RPLND (adjusted annual increase in probability of undergoing robotic vs. open procedure: 16%; 95% CI 8-24). Undergoing robotic RPLND was associated with a reduction in postoperative length of stay of 3.5 days (95% CI 2.9, 4.1). Open surgical approaches comprise the vast majority of RPLNDs performed at pediatric hospitals. This is in contrast with trends in non-pediatric hospitals where robotic RPLND is being increasingly utilized. Future research is necessary to investigate this discrepancy in adopting minimally invasive techniques for RPLND in pediatric centers.


Assuntos
Hospitais Pediátricos/estatística & dados numéricos , Hospitais/estatística & dados numéricos , Laparoscopia/métodos , Excisão de Linfonodo/métodos , Neoplasias Embrionárias de Células Germinativas/cirurgia , Espaço Retroperitoneal/cirurgia , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias Testiculares/cirurgia , Adolescente , Adulto , Estudos de Coortes , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
14.
Sci Transl Med ; 11(489)2019 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-31019025

RESUMO

Bone morphogenetic protein (BMP)/carriers approved for orthopedic procedures achieve efficacy superior or equivalent to autograft bone. However, required supraphysiological BMP concentrations have been associated with potential local and systemic adverse events. Suboptimal BMP/receptor binding and rapid BMP release from approved carriers may contribute to these outcomes. To address these issues and improve efficacy, we engineered chimeras with increased receptor binding by substituting BMP-6 and activin A receptor binding domains into BMP-2 and optimized a carrier for chimera retention and tissue ingrowth. BV-265, a BMP-2/BMP-6/activin A chimera, demonstrated increased binding affinity to BMP receptors, including activin-like kinase-2 (ALK2) critical for bone formation in people. BV-265 increased BMP intracellular signaling, osteogenic activity, and expression of bone-related genes in murine and human cells to a greater extent than BMP-2 and was not inhibited by BMP antagonist noggin or gremlin. BV-265 induced larger ectopic bone nodules in rats compared to BMP-2 and was superior to BMP-2, BMP-2/6, and other chimeras in nonhuman primate bone repair models. A composite matrix (CM) containing calcium-deficient hydroxyapatite granules suspended in a macroporous, fenestrated, polymer mesh-reinforced recombinant human type I collagen matrix demonstrated improved BV-265 retention, minimal inflammation, and enhanced handling. BV-265/CM was efficacious in nonhuman primate bone repair models at concentrations ranging from 1/10 to 1/30 of the BMP-2/absorbable collagen sponge (ACS) concentration approved for clinical use. Initial toxicology studies were negative. These results support evaluations of BV-265/CM as an alternative to BMP-2/ACS in clinical trials for orthopedic conditions requiring augmented healing.


Assuntos
Ativinas/química , Proteína Morfogenética Óssea 6/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Ativinas/farmacologia , Animais , Proteína Morfogenética Óssea 2/metabolismo , Proteína Morfogenética Óssea 6/farmacologia , Proteínas Morfogenéticas Ósseas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Humanos , Osteogênese/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
15.
Nat Rev Microbiol ; 16(10): 629-645, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30181663

RESUMO

Candidate phyla radiation (CPR) bacteria and DPANN (an acronym of the names of the first included phyla) archaea are massive radiations of organisms that are widely distributed across Earth's environments, yet we know little about them. Initial indications are that they are consistently distinct from essentially all other bacteria and archaea owing to their small cell and genome sizes, limited metabolic capacities and often episymbiotic associations with other bacteria and archaea. In this Analysis, we investigate their biology and variations in metabolic capacities by analysis of approximately 1,000 genomes reconstructed from several metagenomics-based studies. We find that they are not monolithic in terms of metabolism but rather harbour a diversity of capacities consistent with a range of lifestyles and degrees of dependence on other organisms. Notably, however, certain CPR and DPANN groups seem to have exceedingly minimal biosynthetic capacities, whereas others could potentially be free living. Understanding of these microorganisms is important from the perspective of evolutionary studies and because their interactions with other organisms are likely to shape natural microbiome function.


Assuntos
Archaea , Bactérias , Fenômenos Fisiológicos Bacterianos/genética , Anaerobiose , Archaea/genética , Archaea/metabolismo , Archaea/fisiologia , Bactérias/genética , Bactérias/metabolismo , Bactérias Anaeróbias , Tamanho Celular , Genoma Arqueal/genética , Genoma Arqueal/fisiologia , Genoma Bacteriano/genética , Genoma Bacteriano/fisiologia , Filogenia , Simbiose
16.
mBio ; 9(2)2018 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-29636439

RESUMO

During the first weeks of life, microbial colonization of the gut impacts human immune system maturation and other developmental processes. In premature infants, aberrant colonization has been implicated in the onset of necrotizing enterocolitis (NEC), a life-threatening intestinal disease. To study the premature infant gut colonization process, genome-resolved metagenomics was conducted on 343 fecal samples collected during the first 3 months of life from 35 premature infants housed in a neonatal intensive care unit, 14 of whom developed NEC, and metaproteomic measurements were made on 87 samples. Microbial community composition and proteomic profiles remained relatively stable on the time scale of a week, but the proteome was more variable. Although genetically similar organisms colonized many infants, most infants were colonized by distinct strains with metabolic profiles that could be distinguished using metaproteomics. Microbiome composition correlated with infant, antibiotics administration, and NEC diagnosis. Communities were found to cluster into seven primary types, and community type switched within infants, sometimes multiple times. Interestingly, some communities sampled from the same infant at subsequent time points clustered with those of other infants. In some cases, switches preceded onset of NEC; however, no species or community type could account for NEC across the majority of infants. In addition to a correlation of protein abundances with organism replication rates, we found that organism proteomes correlated with overall community composition. Thus, this genome-resolved proteomics study demonstrated that the contributions of individual organisms to microbiome development depend on microbial community context.IMPORTANCE Humans are colonized by microbes at birth, a process that is important to health and development. However, much remains to be known about the fine-scale microbial dynamics that occur during the colonization period. We conducted a genome-resolved study of microbial community composition, replication rates, and proteomes during the first 3 months of life of both healthy and sick premature infants. Infants were found to be colonized by similar microbes, but each underwent a distinct colonization trajectory. Interestingly, related microbes colonizing different infants were found to have distinct proteomes, indicating that microbiome function is not only driven by which organisms are present, but also largely depends on microbial responses to the unique set of physiological conditions in the infant gut.


Assuntos
Bactérias/química , Microbioma Gastrointestinal , Hospitalização , Recém-Nascido Prematuro , Microbiota , Proteoma/análise , Bactérias/classificação , Bactérias/genética , Biota , Enterocolite Necrosante/microbiologia , Enterocolite Necrosante/patologia , Fezes/microbiologia , Feminino , Humanos , Recém-Nascido , Masculino , Metagenoma , Metagenômica , Proteômica
18.
Urology ; 111: 186-188, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29030072

RESUMO

Obtaining retrograde access into a ureter that has been previously reimplanted in a cross-trigonal fashion can be a challenging procedure. We describe a percutaneous vesicoscopic approach to obtain access into a reimplanted ureter to perform ureteroscopy and laser lithotripsy.


Assuntos
Cistoscopia , Cálculos Renais/cirurgia , Reimplante/métodos , Ureter/cirurgia , Ureteroscopia/métodos , Adolescente , Cistoscopia/métodos , Humanos , Masculino , Procedimentos Cirúrgicos Urológicos Masculinos/métodos
19.
Microbiome ; 5(1): 72, 2017 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-28693612

RESUMO

BACKGROUND: Establishment of the human gut microbiota begins at birth. This early-life microbiota development can impact host physiology during infancy and even across an entire life span. However, the functional stability and population structure of the gut microbiota during initial colonization remain poorly understood. Metaproteomics is an emerging technology for the large-scale characterization of metabolic functions in complex microbial communities (gut microbiota). RESULTS: We applied a metagenome-informed metaproteomic approach to study the temporal and inter-individual differences of metabolic functions during microbial colonization of preterm human infants' gut. By analyzing 30 individual fecal samples, we identified up to 12,568 protein groups for each of four infants, including both human and microbial proteins. With genome-resolved matched metagenomics, proteins were confidently identified at the species/strain level. The maximum percentage of the proteome detected for the abundant organisms was ~45%. A time-dependent increase in the relative abundance of microbial versus human proteins suggested increasing microbial colonization during the first few weeks of early life. We observed remarkable variations and temporal shifts in the relative protein abundances of each organism in these preterm gut communities. Given the dissimilarity of the communities, only 81 microbial EggNOG orthologous groups and 57 human proteins were observed across all samples. These conserved microbial proteins were involved in carbohydrate, energy, amino acid and nucleotide metabolism while conserved human proteins were related to immune response and mucosal maturation. We identified seven proteome clusters for the communities and showed infant gut proteome profiles were unstable across time and not individual-specific. Applying a gut-specific metabolic module (GMM) analysis, we found that gut communities varied primarily in the contribution of nutrient (carbohydrates, lipids, and amino acids) utilization and short-chain fatty acid production. CONCLUSIONS: Overall, this study reports species-specific proteome profiles and metabolic functions of human gut microbiota during early colonization. In particular, our work contributes to reveal microbiota-associated shifts and variations in the metabolism of three major nutrient sources and short-chain fatty acid during colonization of preterm infant gut.


Assuntos
Microbioma Gastrointestinal , Recém-Nascido Prematuro , Proteômica , Aminoácidos/metabolismo , Proteínas de Bactérias/classificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Metabolismo dos Carboidratos , Ácidos Graxos Voláteis/biossíntese , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiologia , Humanos , Recém-Nascido , Metabolismo dos Lipídeos , Metagenômica , Proteoma , Especificidade da Espécie
20.
ISME J ; 11(12): 2864-2868, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28742071

RESUMO

The number of microbial genomes sequenced each year is expanding rapidly, in part due to genome-resolved metagenomic studies that routinely recover hundreds of draft-quality genomes. Rapid algorithms have been developed to comprehensively compare large genome sets, but they are not accurate with draft-quality genomes. Here we present dRep, a program that reduces the computational time for pairwise genome comparisons by sequentially applying a fast, inaccurate estimation of genome distance, and a slow, accurate measure of average nucleotide identity. dRep achieves a 28 × increase in speed with perfect recall and precision when benchmarked against previously developed algorithms. We demonstrate the use of dRep for genome recovery from time-series datasets. Each metagenome was assembled separately, and dRep was used to identify groups of essentially identical genomes and select the best genome from each replicate set. This resulted in recovery of significantly more and higher-quality genomes compared to the set recovered using co-assembly.


Assuntos
Bactérias/genética , Metagenômica/métodos , Algoritmos , Bactérias/classificação , Bactérias/isolamento & purificação , Genoma Bacteriano , Metagenoma , Metagenômica/instrumentação , Software
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