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1.
Cancer Res ; 84(9): 1396-1403, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38488504

RESUMO

The NCI's Cloud Resources (CR) are the analytical components of the Cancer Research Data Commons (CRDC) ecosystem. This review describes how the three CRs (Broad Institute FireCloud, Institute for Systems Biology Cancer Gateway in the Cloud, and Seven Bridges Cancer Genomics Cloud) provide access and availability to large, cloud-hosted, multimodal cancer datasets, as well as offer tools and workspaces for performing data analysis where the data resides, without download or storage. In addition, users can upload their own data and tools into their workspaces, allowing researchers to create custom analysis workflows and integrate CRDC-hosted data with their own. See related articles by Brady et al., p. 1384, Wang et al., p. 1388, and Kim et al., p. 1404.


Assuntos
Computação em Nuvem , National Cancer Institute (U.S.) , Neoplasias , Humanos , Neoplasias/genética , Estados Unidos , Pesquisa Biomédica , Genômica/métodos , Biologia Computacional/métodos
2.
Cancer Res ; 84(9): 1388-1395, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38488507

RESUMO

Since 2014, the NCI has launched a series of data commons as part of the Cancer Research Data Commons (CRDC) ecosystem housing genomic, proteomic, imaging, and clinical data to support cancer research and promote data sharing of NCI-funded studies. This review describes each data commons (Genomic Data Commons, Proteomic Data Commons, Integrated Canine Data Commons, Cancer Data Service, Imaging Data Commons, and Clinical and Translational Data Commons), including their unique and shared features, accomplishments, and challenges. Also discussed is how the CRDC data commons implement Findable, Accessible, Interoperable, Reusable (FAIR) principles and promote data sharing in support of the new NIH Data Management and Sharing Policy. See related articles by Brady et al., p. 1384, Pot et al., p. 1396, and Kim et al., p. 1404.


Assuntos
Disseminação de Informação , National Cancer Institute (U.S.) , Neoplasias , Humanos , Estados Unidos , Neoplasias/metabolismo , Disseminação de Informação/métodos , Pesquisa Biomédica , Genômica/métodos , Animais , Proteômica/métodos
3.
Nat Med ; 25(3): 530, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30705421

RESUMO

In the version of this article originally published, the color key in Fig. 1a was wrong. In the Cytogenetics key, the box over t(8;21) originally was green. It should have been red, matching the color of the sections of the pie graphs below the key that were labeled with 15% and 19%.

4.
Blood ; 133(12): 1313-1324, 2019 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-30617194

RESUMO

Although generally curable with intensive chemotherapy in resource-rich settings, Burkitt lymphoma (BL) remains a deadly disease in older patients and in sub-Saharan Africa. Epstein-Barr virus (EBV) positivity is a feature in more than 90% of cases in malaria-endemic regions, and up to 30% elsewhere. However, the molecular features of BL have not been comprehensively evaluated when taking into account tumor EBV status or geographic origin. Through an integrative analysis of whole-genome and transcriptome data, we show a striking genome-wide increase in aberrant somatic hypermutation in EBV-positive tumors, supporting a link between EBV and activation-induced cytidine deaminase (AICDA) activity. In addition to identifying novel candidate BL genes such as SIN3A, USP7, and CHD8, we demonstrate that EBV-positive tumors had significantly fewer driver mutations, especially among genes with roles in apoptosis. We also found immunoglobulin variable region genes that were disproportionally used to encode clonal B-cell receptors (BCRs) in the tumors. These include IGHV4-34, known to produce autoreactive antibodies, and IGKV3-20, a feature described in other B-cell malignancies but not yet in BL. Our results suggest that tumor EBV status defines a specific BL phenotype irrespective of geographic origin, with particular molecular properties and distinct pathogenic mechanisms. The novel mutation patterns identified here imply rational use of DNA-damaging chemotherapy in some patients with BL and targeted agents such as the CDK4/6 inhibitor palbociclib in others, whereas the importance of BCR signaling in BL strengthens the potential benefit of inhibitors for PI3K, Syk, and Src family kinases among these patients.


Assuntos
Biomarcadores Tumorais/genética , Linfoma de Burkitt/genética , Infecções por Vírus Epstein-Barr/complicações , Genes de Imunoglobulinas , Genoma Humano , Mutação , Transcriptoma , Adolescente , Adulto , Linfoma de Burkitt/patologia , Linfoma de Burkitt/virologia , Criança , Pré-Escolar , Estudos de Coortes , Citidina Desaminase/genética , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/virologia , Feminino , Seguimentos , Herpesvirus Humano 4/isolamento & purificação , Humanos , Lactente , Recém-Nascido , Masculino , Fenótipo , Prognóstico , Adulto Jovem
5.
Nature ; 562(7727): 373-379, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30209392

RESUMO

Mixed phenotype acute leukaemia (MPAL) is a high-risk subtype of leukaemia with myeloid and lymphoid features, limited genetic characterization, and a lack of consensus regarding appropriate therapy. Here we show that the two principal subtypes of MPAL, T/myeloid (T/M) and B/myeloid (B/M), are genetically distinct. Rearrangement of ZNF384 is common in B/M MPAL, and biallelic WT1 alterations are common in T/M MPAL, which shares genomic features with early T-cell precursor acute lymphoblastic leukaemia. We show that the intratumoral immunophenotypic heterogeneity characteristic of MPAL is independent of somatic genetic variation, that founding lesions arise in primitive haematopoietic progenitors, and that individual phenotypic subpopulations can reconstitute the immunophenotypic diversity in vivo. These findings indicate that the cell of origin and founding lesions, rather than an accumulation of distinct genomic alterations, prime tumour cells for lineage promiscuity. Moreover, these findings position MPAL in the spectrum of immature leukaemias and provide a genetically informed framework for future clinical trials of potential treatments for MPAL.


Assuntos
Leucemia Aguda Bifenotípica/genética , Leucemia Aguda Bifenotípica/patologia , Linhagem da Célula/genética , Análise Mutacional de DNA , Feminino , Variação Genética/genética , Genoma Humano/genética , Genômica , Humanos , Imunofenotipagem , Leucemia Aguda Bifenotípica/classificação , Masculino , Modelos Genéticos , Mutação/genética , Células-Tronco Neoplásicas/imunologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Fenótipo , Transativadores/genética
7.
Nat Med ; 24(1): 103-112, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29227476

RESUMO

We present the molecular landscape of pediatric acute myeloid leukemia (AML) and characterize nearly 1,000 participants in Children's Oncology Group (COG) AML trials. The COG-National Cancer Institute (NCI) TARGET AML initiative assessed cases by whole-genome, targeted DNA, mRNA and microRNA sequencing and CpG methylation profiling. Validated DNA variants corresponded to diverse, infrequent mutations, with fewer than 40 genes mutated in >2% of cases. In contrast, somatic structural variants, including new gene fusions and focal deletions of MBNL1, ZEB2 and ELF1, were disproportionately prevalent in young individuals as compared to adults. Conversely, mutations in DNMT3A and TP53, which were common in adults, were conspicuously absent from virtually all pediatric cases. New mutations in GATA2, FLT3 and CBL and recurrent mutations in MYC-ITD, NRAS, KRAS and WT1 were frequent in pediatric AML. Deletions, mutations and promoter DNA hypermethylation convergently impacted Wnt signaling, Polycomb repression, innate immune cell interactions and a cluster of zinc finger-encoding genes associated with KMT2A rearrangements. These results highlight the need for and facilitate the development of age-tailored targeted therapies for the treatment of pediatric AML.


Assuntos
Leucemia Mieloide Aguda/genética , Mutação , Criança , Aberrações Cromossômicas , Metilação de DNA , Humanos , Transcriptoma
9.
Front Cell Dev Biol ; 5: 83, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28983483

RESUMO

Advancements in next-generation sequencing and other -omics technologies are accelerating the detailed molecular characterization of individual patient tumors, and driving the evolution of precision medicine. Cancer is no longer considered a single disease, but rather, a diverse array of diseases wherein each patient has a unique collection of germline variants and somatic mutations. Molecular profiling of patient-derived samples has led to a data explosion that could help us understand the contributions of environment and germline to risk, therapeutic response, and outcome. To maximize the value of these data, an interdisciplinary approach is paramount. The National Cancer Institute (NCI) has initiated multiple projects to characterize tumor samples using multi-omic approaches. These projects harness the expertise of clinicians, biologists, computer scientists, and software engineers to investigate cancer biology and therapeutic response in multidisciplinary teams. Petabytes of cancer genomic, transcriptomic, epigenomic, proteomic, and imaging data have been generated by these projects. To address the data analysis challenges associated with these large datasets, the NCI has sponsored the development of the Genomic Data Commons (GDC) and three Cloud Resources. The GDC ensures data and metadata quality, ingests and harmonizes genomic data, and securely redistributes the data. During its pilot phase, the Cloud Resources tested multiple cloud-based approaches for enhancing data access, collaboration, computational scalability, resource democratization, and reproducibility. These NCI-led efforts are continuously being refined to better support open data practices and precision oncology, and to serve as building blocks of the NCI Cancer Research Data Commons.

11.
Cancer Res ; 76(8): 2197-205, 2016 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-26941285

RESUMO

The genomic and clinical information used to develop and implement therapeutic approaches for acute myelogenous leukemia (AML) originated primarily from adult patients and has been generalized to patients with pediatric AML. However, age-specific molecular alterations are becoming more evident and may signify the need to age-stratify treatment regimens. The NCI/COG TARGET-AML initiative used whole exome capture sequencing (WXS) to interrogate the genomic landscape of matched trios representing specimens collected upon diagnosis, remission, and relapse from 20 cases of de novo childhood AML. One hundred forty-five somatic variants at diagnosis (median 6 mutations/patient) and 149 variants at relapse (median 6.5 mutations) were identified and verified by orthogonal methodologies. Recurrent somatic variants [in (greater than or equal to) 2 patients] were identified for 10 genes (FLT3, NRAS, PTPN11, WT1, TET2, DHX15, DHX30, KIT, ETV6, KRAS), with variable persistence at relapse. The variant allele fraction (VAF), used to measure the prevalence of somatic mutations, varied widely at diagnosis. Mutations that persisted from diagnosis to relapse had a significantly higher diagnostic VAF compared with those that resolved at relapse (median VAF 0.43 vs. 0.24, P < 0.001). Further analysis revealed that 90% of the diagnostic variants with VAF >0.4 persisted to relapse compared with 28% with VAF <0.2 (P < 0.001). This study demonstrates significant variability in the mutational profile and clonal evolution of pediatric AML from diagnosis to relapse. Furthermore, mutations with high VAF at diagnosis, representing variants shared across a leukemic clonal structure, may constrain the genomic landscape at relapse and help to define key pathways for therapeutic targeting. Cancer Res; 76(8); 2197-205. ©2016 AACR.


Assuntos
Perfilação da Expressão Gênica , Leucemia Mieloide Aguda/genética , Mutação , Adolescente , Criança , Pré-Escolar , Variações do Número de Cópias de DNA , Feminino , Humanos , Lactente , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/patologia , Masculino , Recidiva
12.
Nat Commun ; 6: 10013, 2015 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-26635203

RESUMO

Wilms tumour is an embryonal tumour of childhood that closely resembles the developing kidney. Genomic changes responsible for the development of the majority of Wilms tumours remain largely unknown. Here we identify recurrent mutations within Wilms tumours that involve the highly conserved YEATS domain of MLLT1 (ENL), a gene known to be involved in transcriptional elongation during early development. The mutant MLLT1 protein shows altered binding to acetylated histone tails. Moreover, MLLT1-mutant tumours show an increase in MYC gene expression and HOX dysregulation. Patients with MLLT1-mutant tumours present at a younger age and have a high prevalence of precursor intralobar nephrogenic rests. These data support a model whereby activating MLLT1 mutations early in renal development result in the development of Wilms tumour.


Assuntos
Neoplasias Renais/genética , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Tumor de Wilms/genética , Estudos de Coortes , Histonas/genética , Histonas/metabolismo , Humanos , Rim/metabolismo , Neoplasias Renais/metabolismo , Mutação , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Tumor de Wilms/metabolismo
13.
Appl Environ Microbiol ; 75(7): 2046-56, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19201974

RESUMO

The complete genomes of three strains from the phylum Acidobacteria were compared. Phylogenetic analysis placed them as a unique phylum. They share genomic traits with members of the Proteobacteria, the Cyanobacteria, and the Fungi. The three strains appear to be versatile heterotrophs. Genomic and culture traits indicate the use of carbon sources that span simple sugars to more complex substrates such as hemicellulose, cellulose, and chitin. The genomes encode low-specificity major facilitator superfamily transporters and high-affinity ABC transporters for sugars, suggesting that they are best suited to low-nutrient conditions. They appear capable of nitrate and nitrite reduction but not N(2) fixation or denitrification. The genomes contained numerous genes that encode siderophore receptors, but no evidence of siderophore production was found, suggesting that they may obtain iron via interaction with other microorganisms. The presence of cellulose synthesis genes and a large class of novel high-molecular-weight excreted proteins suggests potential traits for desiccation resistance, biofilm formation, and/or contribution to soil structure. Polyketide synthase and macrolide glycosylation genes suggest the production of novel antimicrobial compounds. Genes that encode a variety of novel proteins were also identified. The abundance of acidobacteria in soils worldwide and the breadth of potential carbon use by the sequenced strains suggest significant and previously unrecognized contributions to the terrestrial carbon cycle. Combining our genomic evidence with available culture traits, we postulate that cells of these isolates are long-lived, divide slowly, exhibit slow metabolic rates under low-nutrient conditions, and are well equipped to tolerate fluctuations in soil hydration.


Assuntos
Bactérias/genética , Bactérias/isolamento & purificação , DNA Bacteriano/genética , Genoma Bacteriano , Microbiologia do Solo , Antibacterianos/biossíntese , Transporte Biológico , Metabolismo dos Carboidratos , Cianobactérias/genética , DNA Bacteriano/química , Fungos/genética , Macrolídeos/metabolismo , Dados de Sequência Molecular , Nitrogênio/metabolismo , Filogenia , Proteobactérias/genética , Análise de Sequência de DNA , Homologia de Sequência
14.
J Bacteriol ; 189(1): 38-51, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17041037

RESUMO

Streptococcus pneumoniae (pneumococcus) is a leading human respiratory pathogen that causes a variety of serious mucosal and invasive diseases. D39 is an historically important serotype 2 strain that was used in experiments by Avery and coworkers to demonstrate that DNA is the genetic material. Although isolated nearly a century ago, D39 remains extremely virulent in murine infection models and is perhaps the strain used most frequently in current studies of pneumococcal pathogenesis. To date, the complete genome sequences have been reported for only two S. pneumoniae strains: TIGR4, a recent serotype 4 clinical isolate, and laboratory strain R6, an avirulent, unencapsulated derivative of strain D39. We report here the genome sequences and new annotation of two different isolates of strain D39 and the corrected sequence of strain R6. Comparisons of these three related sequences allowed deduction of the likely sequence of the D39 progenitor and mutations that arose in each isolate. Despite its numerous repeated sequences and IS elements, the serotype 2 genome has remained remarkably stable during cultivation, and one of the D39 isolates contains only five relatively minor mutations compared to the deduced D39 progenitor. In contrast, laboratory strain R6 contains 71 single-base-pair changes, six deletions, and four insertions and has lost the cryptic pDP1 plasmid compared to the D39 progenitor strain. Many of these mutations are in or affect the expression of genes that play important roles in regulation, metabolism, and virulence. The nature of the mutations that arose spontaneously in these three strains, the relative global transcription patterns determined by microarray analyses, and the implications of the D39 genome sequences to studies of pneumococcal physiology and pathogenesis are presented and discussed.


Assuntos
Genoma Bacteriano , Streptococcus pneumoniae/genética , Animais , Elementos de DNA Transponíveis/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Análise em Microsséries , Dados de Sequência Molecular , Mutação , Infecções Pneumocócicas/microbiologia , Homologia de Sequência do Ácido Nucleico , Streptococcus pneumoniae/patogenicidade , Virulência
15.
J Bacteriol ; 188(19): 6841-50, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16980487

RESUMO

The dimorphic prosthecate bacteria (DPB) are alpha-proteobacteria that reproduce in an asymmetric manner rather than by binary fission and are of interest as simple models of development. Prior to this work, the only member of this group for which genome sequence was available was the model freshwater organism Caulobacter crescentus. Here we describe the genome sequence of Hyphomonas neptunium, a marine member of the DPB that differs from C. crescentus in that H. neptunium uses its stalk as a reproductive structure. Genome analysis indicates that this organism shares more genes with C. crescentus than it does with Silicibacter pomeroyi (a closer relative according to 16S rRNA phylogeny), that it relies upon a heterotrophic strategy utilizing a wide range of substrates, that its cell cycle is likely to be regulated in a similar manner to that of C. crescentus, and that the outer membrane complements of H. neptunium and C. crescentus are remarkably similar. H. neptunium swarmer cells are highly motile via a single polar flagellum. With the exception of cheY and cheR, genes required for chemotaxis were absent in the H. neptunium genome. Consistent with this observation, H. neptunium swarmer cells did not respond to any chemotactic stimuli that were tested, which suggests that H. neptunium motility is a random dispersal mechanism for swarmer cells rather than a stimulus-controlled navigation system for locating specific environments. In addition to providing insights into bacterial development, the H. neptunium genome will provide an important resource for the study of other interesting biological processes including chromosome segregation, polar growth, and cell aging.


Assuntos
Alphaproteobacteria/genética , Caulobacter crescentus/genética , Genoma Bacteriano , Alphaproteobacteria/citologia , Alphaproteobacteria/fisiologia , Proteínas da Membrana Bacteriana Externa/genética , Caulobacter crescentus/citologia , Caulobacter crescentus/fisiologia , Ciclo Celular/genética , Quimiotaxia/genética , Quimiotaxia/fisiologia , DNA Bacteriano/química , DNA Bacteriano/genética , Flagelos/fisiologia , Viabilidade Microbiana , Dados de Sequência Molecular , Movimento , Análise de Sequência de DNA , Homologia de Sequência , Transdução de Sinais
16.
Proc Natl Acad Sci U S A ; 102(39): 13950-5, 2005 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-16172379

RESUMO

The development of efficient and inexpensive genome sequencing methods has revolutionized the study of human bacterial pathogens and improved vaccine design. Unfortunately, the sequence of a single genome does not reflect how genetic variability drives pathogenesis within a bacterial species and also limits genome-wide screens for vaccine candidates or for antimicrobial targets. We have generated the genomic sequence of six strains representing the five major disease-causing serotypes of Streptococcus agalactiae, the main cause of neonatal infection in humans. Analysis of these genomes and those available in databases showed that the S. agalactiae species can be described by a pan-genome consisting of a core genome shared by all isolates, accounting for approximately 80% of any single genome, plus a dispensable genome consisting of partially shared and strain-specific genes. Mathematical extrapolation of the data suggests that the gene reservoir available for inclusion in the S. agalactiae pan-genome is vast and that unique genes will continue to be identified even after sequencing hundreds of genomes.


Assuntos
Genoma Bacteriano , Streptococcus agalactiae/classificação , Streptococcus agalactiae/genética , Sequência de Aminoácidos , Cápsulas Bacterianas/genética , Sequência de Bases , Expressão Gênica , Genes Bacterianos , Variação Genética , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência , Análise de Sequência de DNA , Streptococcus agalactiae/patogenicidade , Virulência/genética
17.
Proc Natl Acad Sci U S A ; 102(31): 10913-8, 2005 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-16043709

RESUMO

The completion of the 5,373,180-bp genome sequence of the marine psychrophilic bacterium Colwellia psychrerythraea 34H, a model for the study of life in permanently cold environments, reveals capabilities important to carbon and nutrient cycling, bioremediation, production of secondary metabolites, and cold-adapted enzymes. From a genomic perspective, cold adaptation is suggested in several broad categories involving changes to the cell membrane fluidity, uptake and synthesis of compounds conferring cryotolerance, and strategies to overcome temperature-dependent barriers to carbon uptake. Modeling of three-dimensional protein homology from bacteria representing a range of optimal growth temperatures suggests changes to proteome composition that may enhance enzyme effectiveness at low temperatures. Comparative genome analyses suggest that the psychrophilic lifestyle is most likely conferred not by a unique set of genes but by a collection of synergistic changes in overall genome content and amino acid composition.


Assuntos
Clima Frio , Gammaproteobacteria/genética , Gammaproteobacteria/metabolismo , Genoma Bacteriano , Aminoácidos/análise , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Carbono/metabolismo , DNA Bacteriano/química , DNA Bacteriano/genética , Metabolismo Energético , Genômica , Biologia Marinha , Fluidez de Membrana , Modelos Biológicos , Dados de Sequência Molecular , Nitrogênio/metabolismo , Proteômica , Especificidade da Espécie
18.
Nat Biotechnol ; 22(5): 554-9, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15077118

RESUMO

Desulfovibrio vulgaris Hildenborough is a model organism for studying the energy metabolism of sulfate-reducing bacteria (SRB) and for understanding the economic impacts of SRB, including biocorrosion of metal infrastructure and bioremediation of toxic metal ions. The 3,570,858 base pair (bp) genome sequence reveals a network of novel c-type cytochromes, connecting multiple periplasmic hydrogenases and formate dehydrogenases, as a key feature of its energy metabolism. The relative arrangement of genes encoding enzymes for energy transduction, together with inferred cellular location of the enzymes, provides a basis for proposing an expansion to the 'hydrogen-cycling' model for increasing energy efficiency in this bacterium. Plasmid-encoded functions include modification of cell surface components, nitrogen fixation and a type-III protein secretion system. This genome sequence represents a substantial step toward the elucidation of pathways for reduction (and bioremediation) of pollutants such as uranium and chromium and offers a new starting point for defining this organism's complex anaerobic respiration.


Assuntos
Desulfovibrio vulgaris/genética , Genoma Bacteriano , Desulfovibrio vulgaris/metabolismo , Metabolismo Energético , Dados de Sequência Molecular
19.
Proc Natl Acad Sci U S A ; 101(15): 5646-51, 2004 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-15064399

RESUMO

We present the complete 2,843,201-bp genome sequence of Treponema denticola (ATCC 35405) an oral spirochete associated with periodontal disease. Analysis of the T. denticola genome reveals factors mediating coaggregation, cell signaling, stress protection, and other competitive and cooperative measures, consistent with its pathogenic nature and lifestyle within the mixed-species environment of subgingival dental plaque. Comparisons with previously sequenced spirochete genomes revealed specific factors contributing to differences and similarities in spirochete physiology as well as pathogenic potential. The T. denticola genome is considerably larger in size than the genome of the related syphilis-causing spirochete Treponema pallidum. The differences in gene content appear to be attributable to a combination of three phenomena: genome reduction, lineage-specific expansions, and horizontal gene transfer. Genes lost due to reductive evolution appear to be largely involved in metabolism and transport, whereas some of the genes that have arisen due to lineage-specific expansions are implicated in various pathogenic interactions, and genes acquired via horizontal gene transfer are largely phage-related or of unknown function.


Assuntos
Genoma Bacteriano , Boca/microbiologia , Treponema/genética , Transportadores de Cassetes de Ligação de ATP/genética , Proteínas de Bactérias/genética , Sequência de Bases , Borrelia burgdorferi/genética , Borrelia burgdorferi/metabolismo , Genes Bacterianos/genética , Leptospira interrogans/genética , Leptospira interrogans/metabolismo , Modelos Genéticos , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Treponema/metabolismo , Treponema/patogenicidade , Treponema pallidum/genética , Treponema pallidum/metabolismo
20.
Proc Natl Acad Sci U S A ; 100(9): 5455-60, 2003 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-12704232

RESUMO

The 1,995,275-bp genome of Coxiella burnetii, Nine Mile phase I RSA493, a highly virulent zoonotic pathogen and category B bioterrorism agent, was sequenced by the random shotgun method. This bacterium is an obligate intracellular acidophile that is highly adapted for life within the eukaryotic phagolysosome. Genome analysis revealed many genes with potential roles in adhesion, invasion, intracellular trafficking, host-cell modulation, and detoxification. A previously uncharacterized 13-member family of ankyrin repeat-containing proteins is implicated in the pathogenesis of this organism. Although the lifestyle and parasitic strategies of C. burnetii resemble that of Rickettsiae and Chlamydiae, their genome architectures differ considerably in terms of presence of mobile elements, extent of genome reduction, metabolic capabilities, and transporter profiles. The presence of 83 pseudogenes displays an ongoing process of gene degradation. Unlike other obligate intracellular bacteria, 32 insertion sequences are found dispersed in the chromosome, indicating some plasticity in the C. burnetii genome. These analyses suggest that the obligate intracellular lifestyle of C. burnetii may be a relatively recent innovation.


Assuntos
Coxiella burnetii/genética , Genoma Bacteriano , Aderência Bacteriana , Coxiella burnetii/fisiologia , Dados de Sequência Molecular
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