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1.
J Cell Mol Med ; 27(22): 3526-3538, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37698037

RESUMO

Exosomal microRNA (miRNA) exerts potential roles in non-small-cell lung cancer (NSCLC). The current study elucidated the role of miR-30b-5p shuttled by bone marrow mesenchymal stem cells (BMSCs)-derived exosomes in treating NSCLC. Bioinformatics analysis was performed with NSCLC-related miRNA microarray GSE169587 and mRNA data GSE74706 obtained for collection of the differentially expressed miRNAs and mRNAs. The relationship between miR-30b-5p and EZH2 was predicted and confirmed. Exosomes were isolated from BMSCs and identified. BMSCs-derived exosomes overexpressing miR-30b-5p were used to establish subcutaneous tumorigenesis models to study the effects of miR-30b-5p, EZH2 and PI3K/AKT signalling pathway on tumour growth. A total of 86 BMSC-exo-miRNAs were differentially expressed in NSCLC. Bioinfomatics analysis found that BMSC-exo-miR-30b-5p could regulate NSCLC progression by targeting EZH2, which was verified by in vitro cell experiments. Besides, the target genes of miR-30b-5p were enriched in PI3K/AKT signalling pathway. Animal experiments validated that BMSC-exo-miR-30b-5p promoted NSCLC cell apoptosis and prevented tumorigenesis in nude mice via EZH2/PI3K/AKT axis. Collectively, the inhibitory role of BMSC-derived exosomes-loaded miR-30b-5p in NSCLC was achieved through blocking the EZH2/PI3K/AKT axis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Exossomos , Neoplasias Pulmonares , Células-Tronco Mesenquimais , MicroRNAs , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Exossomos/metabolismo , Camundongos Nus , Neoplasias Pulmonares/patologia , MicroRNAs/metabolismo , Células-Tronco Mesenquimais/metabolismo , Carcinogênese/patologia
2.
J Cancer Res Clin Oncol ; 149(8): 4639-4651, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36175801

RESUMO

PURPOSE: Serum-derived extracellular vesicles (EVs) have been reported to play an important role in non-small cell lung cancer (NSCLC). The current study sought to explore the effect of serum-EVs delivering m6A methylation regulator heterogeneous nuclear ribonucleoprotein C (HNRNPC) on the development of NSCLC through the regulation of discs large-associated protein 5 (DLGAP5). METHODS: NSCLC-related RNA-Seq and clinical data were first obtained from the TCGA database to screen differentially expressed m6A-related regulators, which were intersected with the differential genes in NSCLC-related microarray GSE43458 obtained from the GEO database for survival analysis and clinical correlation analysis. Correlation between HNRNPC and DLGAP5 expression was evaluated. Serum-EVs were isolated and identified, and the uptake of EVs by A549 cells was visualized using fluorescence microscopy. In vivo xenograft tumor models and tumor metastasis models were constructed in nude mice to observe growth and metastasis of NSCLC cells. RESULTS: HNRNPC was associated with poor prognosis and metastasis of NSCLC, and further implicated in the regulation of DNA replication and cell cycle-related pathways. HNRNPC might promote the growth and metastasis of NSCLC by identifying m6A modification of DLGAP5 mRNA. Serum-EVs delivered HNRNPC to NSCLC cells in vitro. In vivo experimentation further confirmed that serum-EVs could deliver HNRNPC to promote the growth and metastasis of NSCLC cells in nude mice. CONCLUSIONS: Our findings highlight that serum-EVs can deliver HNRNPC to NSCLC cells, wherein HNRNPC recognizes the m6A modification of DLGAP5 mRNA, thus ultimately promoting NSCLC growth and metastasis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Vesículas Extracelulares , Neoplasias Pulmonares , Animais , Camundongos , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Metilação , Ribonucleoproteínas Nucleares Heterogêneas Grupo C/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo C/metabolismo , Camundongos Nus , RNA Mensageiro/genética , Vesículas Extracelulares/metabolismo , Proteínas de Neoplasias/metabolismo
3.
Hum Mol Genet ; 31(23): 4094-4106, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-35848890

RESUMO

High-throughput circular RNA (circRNA) sequencing identified circRNA_001678 (circ_001678) as an upregulated circRNA in non-small cell lung cancer (NSCLC) tissues. Hence, the current study sought to investigate the function and the underlying mechanism of circRNA_001678 in immune escape of NSCLC. Briefly, commercially purchased NSCLC cell lines were adopted for in vitro experiment to evaluate the effects of circ_001678 over-expression or knockdown on cell biological functions, including proliferation, migration and invasive abilities. In addition, the effects of circ_001678 on the in vivo tumorigenicity ability were evaluated for verification. Accordingly, we uncovered that circ_001678 over-expression augmented NSCLC progression in vitro and enhanced tumorigenicity ability in vivo. The interaction between circ_001678 and miR-326 predicted online was verified by means of luciferase and RNA pull-down assays. Furthermore, circ_001678 could sponge miR-326 to up-regulate ZEB1. On the other hand, the tumor-promoting effects of circ_001678 could be inhibited by anti-PD-L1/PD-1 treatment. Mechanistically, circ_001678 led to the activation of the PD-1/PD-L1 pathway to promote CD8+ T cell apoptosis, thereby inducing NSCLC cell immune escape via regulation of the miR-326/ZEB1 axis. To conclude, our findings revealed that circ_001678 sponges miR-326 to up-regulate ZEB1 expression and induce the PD-1/PD-L1 pathway-dependent immune escape, thereby promoting the malignant progression of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Receptor de Morte Celular Programada 1/genética , RNA Circular/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , Proliferação de Células/genética , Linhagem Celular Tumoral , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética
4.
FEBS Open Bio ; 11(8): 2110-2117, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34043884

RESUMO

Overexpression of human dynactin-associated protein isoform a (dynAPa) transforms NIH3T3 cells. DynAPa is a single-pass transmembrane protein with a carboxy-terminal region exposed to the outside of cells. According to the NCBI RefSeq database, there may be two other splicing variants of the encoding gene (dynAPb and c). DynAPa and c differ in some amino-terminal residues (NH2 -MVA in dynAPa and NH2 -MEYQLL in dynAPc). DynAPb has the same amino-terminal residues as dynAPc, but lacks 55 residues in the intracellular region. All three isoforms have the same carboxy-terminal region, including the transmembrane domain. Expression of mRNAs of three splicing variants was found in human cancer cell lines ACHN and Caki-1. The subcellular localization and in vitro cell transformation ability of the three isoforms were examined using NIH3T3 cells overexpressing each respective isoform. All isoforms were found to be localized to the Golgi apparatus and plasma membrane, where the carboxy-terminal region was exposed to the outside of cells. Cell transformation was tested using focus formation due to loss of contact inhibition of cell proliferation, and colony formation was examined on soft agar and spheroid formation in ultralow U-bottomed wells. DynAPa robustly formed foci and colonies on soft agar and spheroid, whereas these abilities were considerably decreased for dynAPb and completely lost in dynAPc. These findings warrant dissection studies to identify the dynAP domain that is required for cell transformation.

6.
J Transl Med ; 19(1): 37, 2021 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-33472665

RESUMO

BACKGROUND: Non-small cell lung cancer (NSCLC) is a common type of lung cancer. Extracellular vehicles (EVs) are nano-sized particles containing proteins, lipids, and miRNAs secreted by various cells, which play important roles in the development of lung cancer by regulating a wide range of signaling pathways. This study focused on elucidating a potential mechanism by which EVs promote the development of NSCLC. METHODS: Expression levels of miR-744, SUV39H1, Smad9, and BMP4 in clinical tissue samples of NSCLC patients and cell lines were quantified by RT-qPCR and/or western blot analysis. The interaction between SUV39H1 and miR-744 was identified by dual-luciferase reporter assay. miR-744, SUV39H1, and BMP4 expression levels were modulated in A549 and H460 cells, in order to evaluate their effects on cell proliferation, colony formation and cell cycle. A NSCLC xenograft mouse model was used to verify the in vitro findings. NSCLC cell-derived EVs and normal bronchial epithelial cell-derived EVs were isolated and their roles in NSCLC development were evaluated in vivo and in vitro. RESULTS: miR-744 expression was lower in cancer cell-derived derived EVs than in normal lung epithelial cell-derived EVs. Reduced miR-744 expression in EVs upregulated SUV39H1 in NSCLC cells and further increased BMP4 levels to promote NSCLC development. BMP4 was upregulated in NSCLC cells upon suppression of Smad9 mediated by SUV39H1. Reduced miR-744 expression transferred from cancer cell-derived EVs into NSCLC cells enhanced cancer development. CONCLUSION: Overall, our findings unveiled a mechanism whereby miR-744 delivered by NSCLC-derived EVs upregulated SUV39H1, activating the Smad9/BMP9 axis and thus promoted cancer development.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Vesículas Extracelulares , Neoplasias Pulmonares , MicroRNAs , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Vesículas Extracelulares/metabolismo , Humanos , Pulmão/metabolismo , Neoplasias Pulmonares/genética , Metiltransferases , Camundongos , MicroRNAs/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteína Smad8
7.
Mol Ther Nucleic Acids ; 18: 166-182, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31557618

RESUMO

Long non-coding RNAs (lncRNAs) have emerged as key regulators of cellular progress in lung adenocarcinoma. In this study, to identify cancer-related lncRNAs and genes, we screened for those lncRNAs that were differentially expressed in lung adenocarcinoma, which revealed LINC00628 overexpression and low expression of laminin subunit alpha 3 (LAMA3). This was further validated in the cancerous tissues from patients diagnosed with lung adenocarcinoma. Thereafter, we explored the functional relevance of LINC00628 and LAMA3 in lung adenocarcinoma by analyzing the recruitment of DNA methyltransferase (DNMT) and the cellular processes of lung adenocarcinoma cells following treatments that induced LINC00628 overexpression or LINC00628 silencing or with 5-azacytidine (5-Aza, a DNMT inhibitor). The results showed that LINC00628 silencing decreased cell proliferation, migration, and invasion as well as the drug resistance of lung adenocarcinoma cells to vincristine (VCR). The results were opposite in the cells with LAMA3 demethylation induced by 5-Aza treatment. Further research indicated that LINC00628 recruited DNMT1, DNMT3A, and DNMT3B to promote the methylation of LAMA3 promoter, thereby decreasing its expression. Moreover, an in vivo experiment was performed in nude mice to assess the tumor growth ability and drug resistance of human lung adenocarcinoma cells. It was observed that LINC00628 silencing or 5-Aza treatment inhibited the in vivo tumor growth ability of the human lung adenocarcinoma cells and reduced their resistance to VCR. Altogether, our results provide evidence of a mechanism by which LINC00628 silencing exerts an inhibitory role in lung adenocarcinoma by modulating the DNA methylation of LAMA3, indicative of a novel molecular target for treatment of lung adenocarcinoma patients showing resistance to VCR.

8.
J Cell Mol Med ; 23(9): 6411-6428, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31317666

RESUMO

Lung adenocarcinoma is a common histologic type of lung cancer with a high death rate globally. Increasing evidence shows that long non-coding RNA H19 (lncRNA H19) and CDH1 methylation are involved in multiple tumours. Here, we tried to investigate whether lncRNA H19 or CDH1 methylation could affect the development of lung adenocarcinoma. First, lung adenocarcinoma tissues were collected to detect CDH1 methylation. Then, the regulatory mechanisms of lncRNA H19 were detected mainly in concert with the treatment of overexpression of lncRNA H19, siRNA against lncRNA H19, overexpression of CDH1 and demethylating agent A-5az in lung adenocarcinoma A549 cell. The expression of lncRNA H19 and epithelial-mesenchymal transition (EMT)-related factors as well as cell proliferation, sphere-forming ability, apoptosis, migration and invasion were detected. Finally, we observed xenograft tumour in nude mice so as to ascertain tumorigenicity of lung adenocarcinoma cells. LncRNA H19 and methylation of CDH1 were highly expressed in lung adenocarcinoma tissues. A549 cells with silencing of lncRNA H19, overexpression of CDH1 or reduced CDH1 methylation by demethylating agent 5-Az had suppressed cell proliferation, sphere-forming ability, apoptosis, migration and invasion, in addition to inhibited EMT process. Silencing lncRNA H19 could reduce methylation level of CDH1. In vivo, A549 cells with silencing lncRNA H19, overexpression of CDH1 or reduced CDH1 methylation exhibited low tumorigenicity, reflected by the smaller tumour size and lighter tumour weight. Taken together, this study demonstrates that silencing of lncRNA H19 inhibits EMT and proliferation while promoting apoptosis of lung adenocarcinoma cells by inhibiting methylation of CDH1 promoter.


Assuntos
Adenocarcinoma de Pulmão/genética , Antígenos CD/genética , Caderinas/genética , Neoplasias Pulmonares/genética , Regiões Promotoras Genéticas/genética , RNA Longo não Codificante/genética , Células A549 , Adulto , Idoso , Animais , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Metilação , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , RNA Interferente Pequeno/genética , Adulto Jovem
9.
Am J Physiol Lung Cell Mol Physiol ; 316(5): L918-L933, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30628487

RESUMO

The involvement of several microRNAs (miRs) in the initiation and development of tumors through the suppression of the target gene expression has been highlighted. The aberrant expression of miR-181d-5p and cyclin-dependent kinase inhibitor 3 (CDKN3) in non-small-cell lung cancer (NSCLC) was then screened by microarray analysis. In the present study, we performed a series of in vivo and in vitro experiments for the purpose of investigating their roles in NSCLC and the underlying mechanism. There was a high expression of CDKN3, whereas miR-181d-5p was downregulated in NSCLC. Quantitative RT-PCR, Western blot analysis, and dual-luciferase reporter gene assay further identified that CDKN3 could be negatively regulated by miR-181d-5p. Moreover, the upregulation of miR-181d-5p or silencing of CDKN3 could inactivate the Akt signaling pathway. A549 with the lowest miR-181d-5p and H1975 with the highest CDKN3 among the five NSCLC cell lines (H1299, A549, H1975, NCI-H157, and GLC-82) were adopted for in vitro experiments, in which expression of miR-181d-5p and CDKN3 was altered by transfection of miR-181d-5p mimic/inhibitor or siRNA-targeting CDKN3. Afterwards, cell proliferation, apoptosis, invasion, migration, and angiogenesis, as well as epithelial-mesenchymal transition (EMT), were evaluated, and tumorigenicity was assessed. In addition, an elevation in miR-181d-5p or depletion in CDKN3 led to significant reductions in proliferation, invasion, migration, angiogenesis, EMT, and tumorigenicity of NSCLC cells, coupling with increased cell apoptosis. In conclusion, this study highlights the tumor-suppressive effects of miR-181d-5p on NSCLC via Akt signaling pathway inactivation by suppressing CDKN3, thus providing a promising therapeutic strategy for the treatment of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proteínas Inibidoras de Quinase Dependente de Ciclina/metabolismo , Fosfatases de Especificidade Dupla/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Proliferação de Células/fisiologia , Proteínas Inibidoras de Quinase Dependente de Ciclina/antagonistas & inibidores , Proteínas Inibidoras de Quinase Dependente de Ciclina/genética , Fosfatases de Especificidade Dupla/antagonistas & inibidores , Fosfatases de Especificidade Dupla/genética , Transição Epitelial-Mesenquimal/genética , Transição Epitelial-Mesenquimal/fisiologia , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Xenoenxertos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Nus , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , Transdução de Sinais
10.
AMB Express ; 8(1): 92, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29858702

RESUMO

High content of lipids in food waste could restrict digestion rate and give rise to the accumulation of long chain fatty acids in anaerobic digester. In the present study, using waste cooking oil skimmed from food waste as the sole carbon source, the effect of organic loading rate (OLR) on the methane production and microbial community dynamics were well investigated. Results showed that stable biomethane production was obtained at an organic loading rate of 0.5-1.5 g VS L-1 days-1. The specific biogas/methane yield values at OLR of 1.0 were 1.44 ± 0.15 and 0.98 ± 0.11 L g VS-1, respectively. The amplicon pyrosequencing revealed the distinct microbial succession in waste cooking oil AD reactors. Acetoclastic methanogens belonging to the genus Methanosaeta were the most dominant archaea, while the genera Syntrophomona, Anaerovibrio and Synergistaceae were the most common bacteria during AD process. Furthermore, redundancy analysis indicated that OLR showed more significant effect on the bacterial communities than that of archaeal communities. Additionally, whether the OLR of lipids increased had slight influence on the acetate fermentation pathway.

11.
Nat Commun ; 5: 4316, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24989825

RESUMO

Directing acoustic waves along curved paths is critical for applications such as ultrasound imaging, surgery and acoustic cloaking. Metamaterials can direct waves by spatially varying the material properties through which the wave propagates. However, this approach is not always feasible, particularly for acoustic applications. Here we demonstrate the generation of acoustic bottle beams in homogeneous space without using metamaterials. Instead, the sound energy flows through a three-dimensional curved shell in air leaving a close-to-zero pressure region in the middle, exhibiting the capability of circumventing obstacles. By designing the initial phase, we develop a general recipe for creating self-bending wave packets, which can set acoustic beams propagating along arbitrary prescribed convex trajectories. The measured acoustic pulling force experienced by a rigid ball placed inside such a beam confirms the pressure field of the bottle. The demonstrated acoustic bottle and self-bending beams have potential applications in medical ultrasound imaging, therapeutic ultrasound, as well as acoustic levitations and isolations.

12.
Wei Sheng Wu Xue Bao ; 48(8): 995-1000, 2008 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-18956745

RESUMO

OBJECTIVE: We studied physiological, biochemical properties and metabolites of Thermoanaerobacter mathranii SC-2 from oil-field water in Shengli oilfield. METHODS: Strain SC-2 was isolated by Hungate anaerobic technique. Through physiological, biochemical and phylogenetic analysis, the strain was identified. Metabolites were analyzed by gas chromatogram. RESULTS: The cells were Gram-negative, rod-shaped, spore-forming. Growth was observed in the temperature range from 40 to 75degrees C (optimum 70 degrees C) and pH range from 5.5 to 9.5 (optimum 6.5). The isolate grew in the presence of 0%-5% NaCl with an optimum without NaCl at pH 7.0 and 65 degrees C. Strain SC-2 used many carbohydrates as carbon sources, including glucose and xylose. Metabolites of glucose were ethanol, acetate, propionate, lactate, CO2 and H2. Based on 16S rDNA studies, strain SC-2 was most close to T. mathranii subsp. mathranii11246T with 99.85% similarity. More ethanol and acetate were produced at initial pH 8.0 than yields at other pH. Yeast extract could significantly increase ethanol and acetate yields. In addition, ethanol (4%) added in the medium obviously inhibited its growth. CONCLUSION: Strain SC-2 was extremely thermophilic, halotolerant anaerobe.


Assuntos
Petróleo/microbiologia , Thermoanaerobacter/isolamento & purificação , Thermoanaerobacter/metabolismo , Microbiologia da Água , Acetatos/metabolismo , Dióxido de Carbono/metabolismo , DNA Bacteriano/genética , DNA Ribossômico/genética , Etanol/metabolismo , Hidrogênio/metabolismo , Concentração de Íons de Hidrogênio , Lactatos/metabolismo , Microscopia Eletrônica , Filogenia , Propionatos/metabolismo , Temperatura , Thermoanaerobacter/classificação , Thermoanaerobacter/ultraestrutura
13.
FEMS Microbiol Lett ; 285(1): 65-71, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18557787

RESUMO

Three strictly anaerobic, thermophilic methanogens (ZC-2T, ZC-3 and ZC-6) were isolated from Shengli oil field, China. The 16S rRNA gene sequences of the three strains were nearly identical, possessing > 99.8% sequence similarity. They also possessed high sequence similarity, 97.4%, to Methanoculleus palmolei strain INSLUZ(T) (97.4% and 97.5%, respectively), indicating that they represented a novel species within the genus Methanoculleus. Cells of strain ZC-2T were nonmotile cocci, 0.8-1.7 microm in diameter, and always occurred singly or in pairs. The three strains used H2/CO2 or sodium formate as substrates for methanogenesis but not sodium acetate, trimethylamine, monomethylamine, ethanol, dimethyl sulfide, isopropanol, isobutanol, butan-2-ol or H2/CO. Optimum growth of strain ZC-2T occurred in the presence of 0.2 M NaCl, pH 7.5-7.8 and temperature 50-55 degrees C with a specific growth rate of 0.084 h(-1). The mol% G+C content of the genomic DNA was 55.2 mol%. Based on these phenotypic and phylogenetic characteristics, strains ZC-2T, ZC-3 and ZC-6 are proposed to represent a novel species in the genus Methanoculleus and named Methanoculleus receptaculi sp. nov. The type strain is ZC-2T (CGMCC 1.5087T=DSM 18860T).


Assuntos
Methanomicrobiaceae/química , Methanomicrobiaceae/isolamento & purificação , Petróleo/microbiologia , Microbiologia da Água , China , DNA Bacteriano/química , DNA Bacteriano/genética , Methanomicrobiaceae/classificação , Methanomicrobiaceae/fisiologia , Dados de Sequência Molecular , Filogenia
14.
Int J Syst Evol Microbiol ; 57(Pt 12): 2964-2969, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18048758

RESUMO

A thermophilic, methylotrophic methanogen, strain ZC-1(T), was isolated from the Shengli oilfield, China. Cells of strain ZC-1(T) were motile cocci, 0.7-1.0 microm in diameter and always occurred in clusters of two to four cells. Lysis-susceptibility experiments and analysis of transmission electron micrographs of strain ZC-1(T) suggested the presence of a proteinaceous cell wall. Strain ZC-1(T) used methanol, methylamine and trimethylamine as substrates for methanogenesis. Optimal growth, with a doubling time of around 5 h, occurred at pH 6.0-6.5, 65 degrees C, 0.3-0.5 M NaCl and 0.05-0.20 M MgCl(2). The DNA G+C content of this organism was 56 mol%. Analysis of 16S rRNA gene sequence and the inferred amino acid sequence of the mcrA gene of strain ZC-1(T) indicated that it is related specifically to members of the family Methanosaetaceae (90.6 and 76.6 % sequence similarity, respectively). However, strain ZC-1(T) failed to grow with acetate as substrate for methanogenesis, which is a special characteristic of the family Methanosaetaceae. Based on these phenotypic and phylogenic characteristics, strain ZC-1(T) is proposed to represent a novel genus and species, for which the name Methermicoccus shengliensis gen. nov., sp. nov. is proposed. The type strain is ZC-1(T) (=CGMCC 1.5056(T)=DSM 18856(T)). Methermicoccaceae fam. nov. is also proposed.


Assuntos
Archaea/classificação , Archaea/isolamento & purificação , Metano/biossíntese , Metanol/metabolismo , Microbiologia da Água , Ácido Acético/metabolismo , Archaea/genética , Archaea/metabolismo , Composição de Bases , China , DNA Arqueal/química , DNA Arqueal/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genes de RNAr , Concentração de Íons de Hidrogênio , Cloreto de Magnésio/metabolismo , Methanosarcinales/genética , Metilaminas/metabolismo , Microscopia Eletrônica , Microscopia de Contraste de Fase , Dados de Sequência Molecular , Petróleo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Cloreto de Sódio/metabolismo , Temperatura
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