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1.
Int J Syst Evol Microbiol ; 66(8): 2944-2951, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27126386

RESUMO

A novel endospore-forming bacterium designated strain GSsed3T was isolated from deposits clogging aboveground filters from the geothermal power platform of Groß Schönebeck in northern Germany. The novel isolate was Gram-staining-positive, facultatively anaerobic, catalase-positive and oxidase-positive. Optimum growth occurred at 60 °C, 0.5 % (w/v) NaCl and pH 7-8. Analysis of the 16S rRNA gene sequence similarity indicated that strain GSsed3T belonged to the genus Anoxybacillus, and showed 99.8 % sequence similarity to Anoxybacillus rupiensis R270T, 98.2 % similarity to Anoxybacillus tepidamans GS5-97T, 97.9 % similarity to Anoxybacillus voinovskiensis TH13T, 97.7 % similarity to Anoxybacillus caldiproteolyticus DSM 15730T and 97.6 % similarity to Anoxybacillus amylolyticus MR3CT. DNA-DNA hybridization (DDH) indicated only 16 % relatedness to Anoxybacillus rupiensis DSM 17127T. Furthermore, DDH estimation based on genomes analysis indicated only 19.9 % overall nucleotide similarity to Anoxybacillus amylolyticus DSM 15939T. The major respiratory menaquinone was MK-8. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unknown phosphoglycolipid and one unknown phospholipid. The predominant cellular fatty acids were iso-C15 : 0, iso-C17 : 0, C16 : 0, iso-C16 : 0 and anteiso-C17 : 0. The peptidoglycan type was A1γ meso-Dpm-direct. The genomic DNA G+C content of the strain was 46.9 mol%. The phenotypic, genotypic and chemotaxonomic characterization indicated that strain GSsed3T differs from related species of the genus. Therefore, strain GSsed3T is considered to be a representative of a novel species of the genus Anoxybacillus, for which the name Anoxybacillus geothermalis sp. nov. is proposed. The type strain of Anoxybacillus geothermalis is GSsed3T (=CCOS808T =ATCC BAA2555T).


Assuntos
Anoxybacillus/classificação , Água Subterrânea/microbiologia , Filogenia , Anoxybacillus/genética , Anoxybacillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Alemanha , Minerais , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , Centrais Elétricas , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
2.
Mol Pharm ; 10(2): 606-18, 2013 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-23281933

RESUMO

Adenovirus type 5 (Ad) is an efficient gene vector with high gene transduction potential, but its efficiency depends on its native cell receptors coxsackie- and adenovirus receptor (CAR) for cell attachment and α(v)ß(3/5) integrins for internalization. To enable transduction of CAR negative cancer cell lines, we have coated the negatively charged Ad by noncovalent charge interaction with cationic PAMAM (polyamidoamine) dendrimers. The specificity for tumor cell infection was increased by targeting the coated Ad to the epidermal growth factor receptor using the peptide ligand GE11, which was coupled to the PAMAM dendrimer via a 2 kDa PEG spacer. Particles were examined by measuring surface charge and size, the degree of coating was determined by transmission electron microscopy. The net positive charge of PAMAM coated Ad enhanced cellular binding and uptake leading to increased transduction efficiency, especially in low to medium CAR expressing cancer cell lines using enhanced green fluorescent protein or luciferase as transgene. While PAMAM coated Ad allowed for efficient internalization, coating with linear polyethylenimine induced excessive particle aggregation, elevated cellular toxicity and lowered transduction efficiency. PAMAM coating of Ad enabled successful transduction of cells in vitro even in the presence of neutralizing antibodies. Taken together, this study clearly proves noncovalent, charge-based coating of Ad vectors with ligand-equipped dendrimers as a viable strategy for efficient transduction of cells otherwise refractory to Ad infection.


Assuntos
Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/metabolismo , Dendrímeros/química , Receptores ErbB/metabolismo , Vetores Genéticos/química , Adenoviridae , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Sobrevivência Celular/fisiologia , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/genética , Receptores ErbB/genética , Citometria de Fluxo , Humanos , Microscopia Eletrônica de Transmissão
3.
Genome Announc ; 3(3)2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26067952

RESUMO

Anoxybacillus geothermalis strain GSsed3 is an endospore-forming thermophilic bacterium isolated from filter deposits in a geothermal site. This novel species has a larger genome size (7.2 Mb) than that of any other Anoxybacillus species, and it possesses genes that support its phenotypic metabolic characterization and suggest an intriguing link to metals.

4.
Front Microbiol ; 4: 209, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23908647

RESUMO

As part of the International Continental Drilling Program deep lake drilling project PaleoVan, we investigated sulfate reduction (SR) in deep sediment cores of the saline, alkaline (salinity 21.4‰, alkalinity 155 m mEq(-1), pH 9.81) Lake Van, Turkey. The cores were retrieved in the Northern Basin (NB) and at Ahlat Ridge (AR) and reached a maximum depth of 220 m. Additionally, 65-75 cm long gravity cores were taken at both sites. SR rates (SRR) were low (≤22 nmol cm(-3) day(-1)) compared to lakes with higher salinity and alkalinity, indicating that salinity and alkalinity are not limiting SR in Lake Van. Both sites differ significantly in rates and depth distribution of SR. In NB, SRR are up to 10 times higher than at AR. SR could be detected down to 19 mblf (meters below lake floor) at NB and down to 13 mblf at AR. Although SRR were lower at AR than at NB, organic matter (OM) concentrations were higher. In contrast, dissolved OM in the pore water at AR contained more macromolecular OM and less low molecular weight OM. We thus suggest, that OM content alone cannot be used to infer microbial activity at Lake Van but that quality of OM has an important impact as well. These differences suggest that biogeochemical processes in lacustrine sediments are reacting very sensitively to small variations in geological, physical, or chemical parameters over relatively short distances.

5.
J Nucl Med ; 54(8): 1450-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23843567

RESUMO

UNLABELLED: Currently, major limitations for the clinical application of adenovirus-mediated gene therapy are high prevalence of neutralizing antibodies, widespread expression of the coxsackie-adenovirus receptor (CAR), and adenovirus sequestration by the liver. In the current study, we used the sodium iodide symporter (NIS) as a theranostic gene to investigate whether coating of adenovirus with synthetic dendrimers could be useful to overcome these hurdles in order to develop adenoviral vectors for combination of systemic oncolytic virotherapy and NIS-mediated radiotherapy. METHODS: We coated replication-deficient (Ad5-CMV/NIS) (CMV is cytomegalovirus) and replication-selective (Ad5-E1/AFP-E3/NIS) adenovirus serotype 5 carrying the hNIS gene with poly(amidoamine) dendrimers generation 5 (PAMAM-G5) in order to investigate transduction efficacy and altered tropism of these coated virus particles by (123)I scintigraphy and to evaluate their therapeutic potential for systemic radiovirotherapy in a liver cancer xenograft mouse model. RESULTS: After dendrimer coating, Ad5-CMV/NIS demonstrated partial protection from neutralizing antibodies and enhanced transduction efficacy in CAR-negative cells in vitro. In vivo (123)I scintigraphy of nude mice revealed significantly reduced levels of hepatic transgene expression after intravenous injection of dendrimer-coated Ad5-CMV/NIS (dcAd5-CMV/NIS). Evasion from liver accumulation resulted in significantly reduced liver toxicity and increased transduction efficiency of dcAd5-CMV/NIS in hepatoma xenografts. After PAMAM-G5 coating of the replication-selective Ad5-E1/AFP-E3/NIS, a significantly enhanced oncolytic effect was observed after intravenous application (virotherapy) that was further increased by additional treatment with a therapeutic dose of (131)I (radiovirotherapy) and was associated with markedly improved survival. CONCLUSION: These results demonstrate efficient liver detargeting and tumor retargeting of adenoviral vectors after coating with synthetic dendrimers, thereby representing a promising innovative strategy for systemic NIS gene therapy. Moreover, our study-based on the function of NIS as a theranostic gene allowing the noninvasive imaging of NIS expression by (123)I scintigraphy-provides detailed characterization of in vivo vector biodistribution and localization, level, and duration of transgene expression, essential prerequisites for exact planning and monitoring of clinical gene therapy trials that aim to individualize the NIS gene therapy concept.


Assuntos
Adenoviridae/genética , Dendrímeros/metabolismo , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/virologia , Terapia Viral Oncolítica/métodos , Radioterapia Guiada por Imagem/métodos , Simportadores/genética , Adenoviridae/metabolismo , Adenoviridae/fisiologia , Animais , Linhagem Celular Tumoral , Humanos , Radioisótopos do Iodo/uso terapêutico , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Camundongos , Cintilografia , Transdução Genética
6.
Mol Ther Nucleic Acids ; 2: e131, 2013 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-24193032

RESUMO

We recently demonstrated tumor-selective iodide uptake and therapeutic efficacy of combined radiovirotherapy after systemic delivery of the theranostic sodium iodide symporter (NIS) gene using a dendrimer-coated adenovirus. To further improve shielding and targeting we physically coated replication-selective adenoviruses carrying the hNIS gene with a conjugate consisting of cationic poly(amidoamine) (PAMAM) dendrimer linked to the peptidic, epidermal growth factor receptor (EGFR)-specific ligand GE11. In vitro experiments demonstrated coxsackie-adenovirus receptor-independent but EGFR-specific transduction efficiency. Systemic injection of the uncoated adenovirus in a liver cancer xenograft mouse model led to high levels of NIS expression in the liver due to hepatic sequestration, which were significantly reduced after coating as demonstrated by (123)I-scintigraphy. Reduction of adenovirus liver pooling resulted in decreased hepatotoxicity and increased transduction efficiency in peripheral xenograft tumors. (124)I-PET-imaging confirmed EGFR-specificity by significantly lower tumoral radioiodine accumulation after pretreatment with the EGFR-specific antibody cetuximab. A significantly enhanced oncolytic effect was observed following systemic application of dendrimer-coated adenovirus that was further increased by additional treatment with a therapeutic dose of (131)I. These results demonstrate restricted virus tropism and tumor-selective retargeting after systemic application of coated, EGFR-targeted adenoviruses therefore representing a promising strategy for improved systemic adenoviral NIS gene therapy.Molecular Therapy-Nucleic Acids (2013) 2, e131; doi:10.1038/mtna.2013.58; published online 5 November 2013.

7.
Am Ann Deaf ; 155(3): 369-76, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21138049

RESUMO

Integration experiences of hearing impaired German elementary school students in separate educational settings (n = 31) were compared with those of counterparts at the same level in integrated settings (n = 26), and evaluated in regard to psychosocial behavior, semantic-lexical abilities, and communicative skills. Analysis of questionnaire responses and intelligence subtests showed that the only difference between the samples concerned perceived well-being in school, and favored the integrated students. Other percentages of variance are explainable by school type (10%), parents' hearing status (12%), and use of bimodal communication (11%). The integrated students demonstrated a higher level of integration experience, associated with fewer psychosocial abnormalities and better communicative skills. The results indicate that educational setting is not the only factor influencing students' perceived well-being. Other contextual factors, e.g., hearing status of parents and communicative skills, have a similar positive impact on integration experiences


Assuntos
Comportamento Infantil , Educação de Pessoas com Deficiência Auditiva , Educação Inclusiva , Aprendizagem , Inclusão Escolar , Estudantes , Criança , Comunicação , Feminino , Alemanha , Humanos , Testes de Inteligência , Masculino , Relações Pais-Filho , Pessoas com Deficiência Auditiva/psicologia , Meio Social , Estudantes/psicologia , Inquéritos e Questionários
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