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1.
Microorganisms ; 11(9)2023 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-37763986

RESUMEN

The identification of pathogens associated with respiratory symptoms other than the novel coronavirus disease 2019 (COVID-19) can be challenging. However, the diagnosis of pathogens is crucial for assessing the clinical outcome of patients. We comprehensively profiled pathogens causing non-COVID-19 respiratory symptoms during the 7th prevalent period in Gunma, Japan, using deep sequencing combined with a next-generation sequencer (NGS) and advanced bioinformatics technologies. The study included nasopharyngeal swabs from 40 patients who tested negative for severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) using immuno-chromatography and/or quantitative reverse transcription polymerase chain reaction (qRT-PCR) methods. Comprehensive pathogen sequencing was conducted through deep sequencing using NGS. Additionally, short reads obtained from NGS were analyzed for comprehensive pathogen estimation using MePIC (Metagenomic Pathogen Identification Pipeline for Clinical Specimens) and/or VirusTap. The results revealed the presence of various pathogens, including respiratory viruses and bacteria, in the present subjects. Notably, human adenovirus (HAdV) was the most frequently detected virus in 16 of the 40 cases (40.0%), followed by coryneforms, which were the most frequently detected bacteria in 21 of the 40 cases (52.5%). Seasonal human coronaviruses (NL63 type, 229E type, HKU1 type, and OC43 type), human bocaviruses, and human herpesviruses (human herpesvirus types 1-7) were not detected. Moreover, multiple pathogens were detected in 50% of the subjects. These results suggest that various respiratory pathogens may be associated with non-COVID-19 patients during the 7th prevalent period in Gunma Prefecture, Japan. Consequently, for an accurate diagnosis of pathogens causing respiratory infections, detailed pathogen analyses may be necessary. Furthermore, it is possible that various pathogens, excluding SARS-CoV-2, may be linked to fever and/or respiratory infections even during the COVID-19 pandemic.

2.
J Clin Immunol ; 35(4): 384-98, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25875699

RESUMEN

OBJECTIVE: We here describe treatment outcomes in two adenosine deaminase (ADA)-deficiency patients (pt) who received stem cell gene therapy (SCGT) with no cytoreductive conditioning. As this protocol has features distinct from those of other clinical trials, its results provide insights into SCGT for ADA deficiency. PATIENTS AND METHODS: Pt 1 was treated at age 4.7 years, whereas pt 2, who had previously received T-cell gene therapy, was treated at age 13 years. Bone marrow CD34(+) cells were harvested after enzyme replacement therapy (ERT) was withdrawn; following transduction of ADA cDNA by the γ-retroviral vector GCsapM-ADA, they were administered intravenously. No cytoreductive conditioning, at present considered critical for therapeutic benefit, was given before cell infusion. Hematological/immunological reconstitution kinetics, levels of systemic detoxification, gene-marking levels, and proviral insertion sites in hematopoietic cells were assessed. RESULTS: Treatment was well tolerated, and no serious adverse events were observed. Engraftment of gene-modified repopulating cells was evidenced by the appearance and maintenance of peripheral lymphocytes expressing functional ADA. Systemic detoxification was moderately achieved, allowing temporary discontinuation of ERT for 6 and 10 years in pt 1 and pt 2, respectively. Recovery of immunity remained partial, with lymphocyte counts in pts 1 and 2, peaked at 408/mm(3) and 1248/mm(3), approximately 2 and 5 years after SCGT. Vector integration site analyses confirmed that hematopoiesis was reconstituted with a limited number of clones, some of which were shown to have myelo-lymphoid potential. CONCLUSIONS: Outcomes in SCGT for ADA-SCID are described in the context of a unique protocol, which used neither ERT nor cytoreductive conditioning. Although proven safe, immune reconstitution was partial and temporary. Our results reiterate the importance of cytoreductive conditioning to ensure greater benefits from SCGT.


Asunto(s)
Adenosina Desaminasa/deficiencia , Adenosina Desaminasa/genética , Agammaglobulinemia/genética , Agammaglobulinemia/terapia , Terapia Genética , Trasplante de Células Madre Hematopoyéticas , Inmunodeficiencia Combinada Grave/genética , Inmunodeficiencia Combinada Grave/terapia , Adenosina Desaminasa/inmunología , Adenosina Desaminasa/uso terapéutico , Adolescente , Agammaglobulinemia/diagnóstico , Agammaglobulinemia/inmunología , Edad de Inicio , Diferenciación Celular , Preescolar , Activación Enzimática , Terapia de Reemplazo Enzimático , Gammaretrovirus/genética , Expresión Génica , Vectores Genéticos/genética , Hematopoyesis , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Humanos , Inmunidad , Inmunofenotipificación , Lactante , Recién Nacido , Japón , Subgrupos Linfocitarios/inmunología , Subgrupos Linfocitarios/metabolismo , Mutación , Inmunodeficiencia Combinada Grave/diagnóstico , Inmunodeficiencia Combinada Grave/inmunología , Transducción Genética , Transgenes , Resultado del Tratamiento
3.
Extremophiles ; 11(6): 819-26, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17618403

RESUMEN

Proteomic analysis of a cold-adapted bacterium, Shewanella livingstonensis Ac10, isolated from Antarctic seawater was carried out to elucidate its cold-adaptation mechanism. The cells were grown at 4 degrees C and 18 degrees C, and soluble and membrane proteins were analyzed by two-dimensional gel electrophoresis. At 4 degrees C, the relative abundance of 47 soluble proteins and five membrane proteins increased more than twofold, and these proteins were analyzed by peptide mass fingerprinting. Twenty-six soluble proteins and two membrane proteins were identified. These included proteins involved in RNA synthesis and folding (RpoA, GreA, and CspA), protein synthesis and folding (TufB, Efp, LysU, and Tig), membrane transport (OmpA and OmpC), and motility (FlgE and FlgL). Cold-inducible RpoA, GreA, and CspA may be required for efficient and accurate transcription and proper folding of RNA at low temperatures, where base pairing of nucleic acids is stable and undesired secondary structures of RNA tend to form. Tig is supposed to have peptidyl-prolyl cis-trans isomerase activity and facilitate proper folding of proteins at low temperatures. The cold induction of OmpA and OmpC is likely to counteract the low diffusion rate of solutes at low temperatures and enables the efficient uptake of nutrients. These results provided many clues to understand microbial cold-adaptation mechanisms.


Asunto(s)
Adaptación Fisiológica , Proteínas Bacterianas/metabolismo , Frío , Proteómica , Shewanella/metabolismo , Adaptación Fisiológica/genética , Regiones Antárticas , Proteínas Bacterianas/genética , Electroforesis en Gel Bidimensional , Regulación Bacteriana de la Expresión Génica , Mapeo Peptídico , Proteómica/métodos , ARN Bacteriano/metabolismo , ARN Mensajero/metabolismo , Agua de Mar/microbiología , Shewanella/genética , Shewanella/crecimiento & desarrollo , Factores de Tiempo , Transcripción Genética , Microbiología del Agua
4.
Curr Biol ; 17(10): 881-6, 2007 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-17493812

RESUMEN

Although dense animal communities at hydrothermal vents and cold seeps rely on symbioses with chemoautotrophic bacteria [1, 2], knowledge of the mechanisms underlying these chemosynthetic symbioses is still fragmentary because of the difficulty in culturing the symbionts and the hosts in the laboratory. Deep-sea Calyptogena clams harbor thioautotrophic bacterial symbionts in their gill epithelial cells [1, 2]. They have vestigial digestive tracts and nutritionally depend on their symbionts [3], which are vertically transmitted via eggs [4]. To clarify the symbionts' metabolic roles in the symbiosis and adaptations to intracellular conditions, we present the complete genome sequence of the symbiont of Calyptogena okutanii. The genome is a circular chromosome of 1,022,154 bp with 31.6% guanine + cytosine (G + C) content, and is the smallest reported genome in autotrophic bacteria. It encodes 939 protein-coding genes, including those for thioautotrophy and for the syntheses of almost all amino acids and various cofactors. However, transporters for these substances to the host cell are apparently absent. Genes that are unnecessary for an intracellular lifestyle, as well as some essential genes (e.g., ftsZ for cytokinesis), appear to have been lost from the symbiont genome. Reductive evolution of the genome might be ongoing in the vertically transmitted Calyptogena symbionts.


Asunto(s)
Bacterias/genética , Bivalvos/microbiología , Genoma Bacteriano , Animales , Procesos Autotróficos , Bacterias/clasificación , Bacterias/metabolismo , Transporte Biológico , Carbono/metabolismo , Metabolismo Energético , Funciones de Verosimilitud , Azufre/metabolismo , Simbiosis
5.
Appl Environ Microbiol ; 73(15): 4849-56, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17526788

RESUMEN

A recombinant protein expression system working at low temperatures is expected to be useful for the production of thermolabile proteins. We constructed a low-temperature expression system using an Antarctic cold-adapted bacterium, Shewanella sp. strain Ac10, as the host. We evaluated the promoters for proteins abundantly produced at 4 degrees C in this bacterium to express foreign proteins. We used 27 promoters and a broad-host-range vector, pJRD215, to produce beta-lactamase in Shewanella sp. strain Ac10. The maximum yield was obtained when the promoter for putative alkyl hydroperoxide reductase (AhpC) was used and the recombinant cells were grown to late stationary phase. The yield was 91 mg/liter of culture at 4 degrees C and 139 mg/liter of culture at 18 degrees C. We used this system to produce putative peptidases, PepF, LAP, and PepQ, and a putative glucosidase, BglA, from a psychrophilic bacterium, Desulfotalea psychrophila DSM12343. We obtained 48, 7.1, 28, and 5.4 mg/liter of culture of these proteins, respectively, in a soluble fraction. The amounts of PepF and PepQ produced by this system were greater than those produced by the Escherichia coli T7 promoter system.


Asunto(s)
Adaptación Fisiológica , Proteínas Bacterianas/metabolismo , Frío , Regulación Bacteriana de la Expresión Génica , Proteínas Recombinantes/metabolismo , Shewanella/enzimología , Proteínas Bacterianas/genética , Biotecnología/métodos , Cartilla de ADN , Deltaproteobacteria/enzimología , Deltaproteobacteria/genética , Glucosidasas/genética , Glucosidasas/metabolismo , Respuesta al Choque Térmico , Péptido Hidrolasas/genética , Péptido Hidrolasas/metabolismo , Proteínas Recombinantes/genética , Shewanella/genética , Shewanella/fisiología
6.
Genome Res ; 16(5): 686-91, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16606699

RESUMEN

Protein-protein interactions play key roles in protein function and the structural organization of a cell. A thorough description of these interactions should facilitate elucidation of cellular activities, targeted-drug design, and whole cell engineering. A large-scale comprehensive pull-down assay was performed using a His-tagged Escherichia coli ORF clone library. Of 4339 bait proteins tested, partners were found for 2667, including 779 of unknown function. Proteins copurifying with hexahistidine-tagged baits on a Ni2+-NTA column were identified by MALDI-TOF MS (matrix-assisted laser desorption ionization time of flight mass spectrometry). An extended analysis of these interacting networks by bioinformatics and experimentation should provide new insights and novel strategies for E. coli systems biology.


Asunto(s)
Escherichia coli K12/química , Proteínas de Escherichia coli/metabolismo , Proteoma/análisis , Proteínas de Escherichia coli/química , Biblioteca de Genes , Histidina/química , Modelos Biológicos , Sistemas de Lectura Abierta , Proteómica , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
7.
DNA Res ; 12(1): 63-8, 2005 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-16106753

RESUMEN

To facilitate genetic studies of Escherichia coli, we constructed a complete set of mobile plasmid clones of intact open reading frames (ORFs). Their expression is strictly controlled by Ptac / lacI(q). The plasmids carrying each ORF were introduced into an F+ recA strain and stored in 96-well microtiter plates. In this way, 96 clones can be transferred simultaneously to F- bacteria using the conjugative system. This provides a convenient procedure for systematic identification of ORFs that suppress or complement mutations. We created two types of clone sets: the original set contained individual clones in 45 microtiter plates, and a second set contained pools of 48 clones stored in a single microtiter plate. Using these clone sets, we have identified 403 genes that can correct in trans the temperature-sensitive defect of cell division mutants, which would suggest multiple global regulators for bacterial cell division.


Asunto(s)
Escherichia coli/genética , Sistemas de Lectura Abierta/genética , Plásmidos , Secuencia de Bases , División Celular/genética , Clonación Molecular , Genes Bacterianos , Prueba de Complementación Genética/métodos , Modelos Genéticos , Datos de Secuencia Molecular
8.
DNA Res ; 12(5): 291-9, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16769691

RESUMEN

Based on the genomic sequence data of Escherichia coli K-12 strain, we have constructed a complete set of cloned individual genes encoding Histidine-tagged proteins with or without GFP fused for functional genomic analysis. Each clone encodes a protein of predicted ORF attached by Histidines and seven spacer amino acids at the N-terminal end, and five spacer amino acids and GFP at the C-terminal end. SfiI restriction sites are generated at both the N- and C-terminal boundaries of ORF upon cloning, which enables easy transfer of ORF to other vector systems by cutting with SfiI. Expression of cloned ORF is under the control of an IPTG-inducible promoter, which is strictly repressed by lacI(q) repressor gene product. The set of cloned ORFs described here should provide unique resources for systematic functional genomic approaches including (i) construction of DNA microarray, (ii) production and purification of proteins, (iii) analysis of protein localization by monitoring GFP fluorescence and (iv) analysis of protein-protein interaction.


Asunto(s)
Escherichia coli K12/genética , Proteínas de Escherichia coli/genética , Biblioteca de Genes , Sistemas de Lectura Abierta , Escherichia coli K12/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Histidina/química , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo
9.
J Biol Chem ; 279(52): 54687-94, 2004 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-15489502

RESUMEN

To find proteins with nucleotidase activity in Escherichia coli, purified unknown proteins were screened for the presence of phosphatase activity using the general phosphatase substrate p-nitrophenyl phosphate. Proteins exhibiting catalytic activity were then assayed for nucleotidase activity against various nucleotides. These screens identified the presence of nucleotidase activity in three uncharacterized E. coli proteins, SurE, YfbR, and YjjG, that belong to different enzyme superfamilies: SurE-like family, HD domain family (YfbR), and haloacid dehalogenase (HAD)-like superfamily (YjjG). The phosphatase activity of these proteins had a neutral pH optimum (pH 7.0-8.0) and was strictly dependent on the presence of divalent metal cations (SurE: Mn(2+) > Co(2+) > Ni(2+) > Mg(2+); YfbR: Co(2+) > Mn(2+) > Cu(2+); YjjG: Mg(2+) > Mn(2+) > Co(2+)). Further biochemical characterization of SurE revealed that it has a broad substrate specificity and can dephosphorylate various ribo- and deoxyribonucleoside 5'-monophosphates and ribonucleoside 3'-monophosphates with highest affinity to 3'-AMP. SurE also hydrolyzed polyphosphate (exopolyphosphatase activity) with the preference for short-chain-length substrates (P(20-25)). YfbR was strictly specific to deoxyribonucleoside 5'-monophosphates, whereas YjjG showed narrow specificity to 5'-dTMP, 5'-dUMP, and 5'-UMP. The three enzymes also exhibited different sensitivities to inhibition by various nucleoside di- and triphosphates: YfbR was equally sensitive to both di- and triphosphates, SurE was inhibited only by triphosphates, and YjjG was insensitive to these effectors. The differences in their sensitivities to nucleotides and their varied substrate specificities suggest that these enzymes play unique functions in the intracellular nucleotide metabolism in E. coli.


Asunto(s)
Fosfatasa Ácida/análisis , Proteínas de Escherichia coli/análisis , Escherichia coli/enzimología , N-Glicosil Hidrolasas/análisis , Nucleotidasas/análisis , Fosfatasa Ácida/antagonistas & inhibidores , Fosfatasa Ácida/metabolismo , Cationes Bivalentes/farmacología , Desoxirribonucleótidos/metabolismo , Inhibidores Enzimáticos/farmacología , Proteínas de Escherichia coli/antagonistas & inhibidores , Proteínas de Escherichia coli/metabolismo , Concentración de Iones de Hidrógeno , Hidrólisis , Cinética , N-Glicosil Hidrolasas/antagonistas & inhibidores , N-Glicosil Hidrolasas/metabolismo , Nucleotidasas/antagonistas & inhibidores , Nucleotidasas/metabolismo , Nucleótidos/metabolismo , Nucleótidos/farmacología , Monoéster Fosfórico Hidrolasas/metabolismo , Polifosfatos/metabolismo , Ribonucleótidos/metabolismo , Especificidad por Sustrato
10.
DNA Res ; 11(1): 27-35, 2004 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-15141943

RESUMEN

We performed threefold shotgun sequencing of the silkworm (Bombyx mori) genome to obtain a draft sequence and establish a basic resource for comprehensive genome analysis. By using the newly developed RAMEN assembler, the sequence data derived from whole-genome shotgun (WGS) sequencing were assembled into 49,345 scaffolds that span a total length of 514 Mb including gaps and 387 Mb without gaps. Because the genome size of the silkworm is estimated to be 530 Mb, almost 97% of the genome has been organized in scaffolds, of which 75% has been sequenced. By carrying out a BLAST search for 50 characteristic Bombyx genes and 11,202 non-redundant expressed sequence tags (ESTs) in a Bombyx EST database against the WGS sequence data, we evaluated the validity of the sequence for elucidating the majority of silkworm genes. Analysis of the WGS data revealed that the silkworm genome contains many repetitive sequences with an average length of <500 bp. These repetitive sequences appear to have been derived from truncated transposons, which are interspersed at 2.5- to 3-kb intervals throughout the genome. This pattern suggests that silkworm may have an active mechanism that promotes removal of transposons from the genome. We also found evidence for insertions of mitochondrial DNA fragments at 9 sites. A search for Bombyx orthologs to Drosophila genes controlling sex determination in the WGS data revealed 11 Bombyx genes and suggested that the sex-determining systems differ profoundly between the two species.


Asunto(s)
Bombyx/genética , Etiquetas de Secuencia Expresada , Biblioteca de Genes , Genoma , Animales , Biología Computacional , Bases de Datos Genéticas
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