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1.
Artigo em Inglês | MEDLINE | ID: mdl-34582328

RESUMO

A strictly anaerobic, thermophilic, Gram-stain-negative bacterium, named as strain S15T, was isolated from oily sludge of Shengli oilfield in PR China. Cells of strain S15T were straight or slightly curved rods with 0.4-0.8 µm width × 1.4-3 µm length and occurred mostly in pairs or short chains. Endospore-formation was not observed. The strain grew optimally at 55 °C (range from 30-65 °C), pH 6.5 (pH 6.0-8.5) and 0-30 g l-1 NaCl (optimum with 10 g l-1 NaCl). Yeast extract was an essential growth factor for strain S15T. The major cellular fatty acid was iso-C15 : 0 (58.2 %), and the main polar lipids were amino phospholipid (APL), glycolipids (GLs) and phosphatidylethanolamine (PE). The G+C content of DNA of strain S15T was 52.2 mol%. Strain S15T shared 89.8 % 16S rRNA gene similarity with the most related organism Acetomicrobium hydrogeniformans DSM 22491T in the phylum Synergistetes. The paired genomic average amino acid identity (AAI) and percentage of conserved proteins (POCP) values showed relatedness of less than 58.0 and 39.7 % with type strains of the species in the phylum Synergistetes. On the basis of phenotypic, phylogenetic and phylogenomic evidences, strain S15T constitutes a novel species in a novel genus, for the name Thermosynergistes pyruvativorans gen. nov., sp. nov. is proposed. The type strain is S15T (=CCAM 583T=JCM 33159T). Thermosynergistaceae fam. nov. is also proposed.


Assuntos
Campos de Petróleo e Gás , Ácido Pirúvico , Anaerobiose , Bactérias , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
2.
Int J Syst Evol Microbiol ; 70(5): 3361-3373, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375973

RESUMO

A novel obligately anaerobic, thermophilic and formate-utilizing bacterium K32T was isolated from Shengli oilfield of China. Cells were straight rods (0.4-0.8 µm × 2.5-8.0 µm), Gram-stain-positive, non-spore-forming and slightly motile. Optimum growth occurred with pH of 7 and 0.5 g l-1 NaCl under temperature of 55-60 °C. Nitrate could be reduced into nitrite, syntrophic formate oxidation to methane and carbon dioxide occurred when co-culturing strain K32T and Methanothermobacter thermautotrophicus ΔH. The main cellular fatty acids were iso-C15 : 0 (24.0 %), anteiso-C15 : 0 (21.7 %), C16 : 0 (12.7 %) and C14 : 0 (10.8 %), and the main polar lipid was phosphatidylglycerol. The G+C content of the genomic DNA was 46.3 mol%. The 16S rRNA gene sequence of K32T shared ≤90.4 % of sequence similarity to closest type strains of Desulfitibacter alkalitolerans, Calderihabitans maritimus and members of the genus Moorella. Based on the phenotypic, biochemical and genotypic characterization, Zhaonella formicivorans gen. nov., sp. nov. is proposed with K32T (=CCAM 584T =DSM 107278T=CGMCC1.5297T) as the type strain, which is the first representative of Zhaonellaceae fam. nov. In addition, the order Thermoanaerobacterales and family Peptococcaceae were reclassified, and three novel families in the novel order of Moorellales ord. nov. were also proposed.


Assuntos
Firmicutes/classificação , Formiatos/metabolismo , Campos de Petróleo e Gás/microbiologia , Filogenia , Anaerobiose , Bactérias Anaeróbias/classificação , Bactérias Anaeróbias/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Firmicutes/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
3.
Sci Rep ; 9(1): 17396, 2019 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-31758023

RESUMO

Propionate is one of the most important intermediates of anaerobic fermentation. Its oxidation performed by syntrophic propionate-oxidizing bacteria coupled with hydrogenotrophic methanogens is considered to be a rate-limiting step for methane production. However, the current understanding of SPOB is limited due to the difficulty of pure culture isolation. In the present study, two anaerobic chemostats fed with propionate as the sole carbon source were operated at different dilution rates (0.05 d-1 and 0.15 d-1). The propionate- and acetate-oxidizing bacteria in the two methanogenic chemostats were investigated combining DNA-stable isotope probing (DNA-SIP) and 16S rRNA gene high-throughput sequencing. The results of DNA-SIP with 13C-propionate/acetate suggested that, Smithella, Syntrophobacter, Cryptanaerobacter, and unclassified Rhodospirillaceae may be putative propionate-oxidizing bacteria; unclassified Spirochaetaceae, unclassified Synergistaceae, unclassified Elusimicrobia, Mesotoga, and Gracilibacter may contribute to acetate oxidation; unclassified Syntrophaceae and Syntrophomonas may be butyrate oxidizers. By DNA-SIP, unclassified OTUs with 16S rRNA gene abundance higher than 62% of total Bacteria in the PL chemostat and 38% in the PH chemostat were revealed to be related to the degradation of propionate. These results suggest that a variety of uncultured bacteria contribute to propionate degradation during anaerobic digestion. The functions and metabolic characteristics of these bacteria require further investigation.


Assuntos
Acetatos/metabolismo , Bactérias/isolamento & purificação , Reatores Biológicos/microbiologia , DNA/química , Marcação por Isótopo/métodos , Propionatos/metabolismo , Anaerobiose/fisiologia , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental , Sondas de DNA/química , Microbiologia Ambiental , Fermentação , Microbiota/genética , Oxirredução , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética
4.
Int J Syst Evol Microbiol ; 69(12): 3891-3902, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31513009

RESUMO

A Gram-stain-negative, rod-shaped, chemoorganotrophic and anaerobic bacterium, strain SK-G1T, was isolated from oily sludge sampled at the Shengli oilfield in PR China. Growth occurred with 0-30 g l-1 NaCl, at 40-65 °C and at pH 6.0-8.5. The predominant fatty acids were C14 : 0 and C13 : 0, and the major cellular polar lipids were phosphatidylglycerol and phosphatidylethanolamine. No respiratory quinone was detected. The genomic G+C content was 43.9 mol%. The strain had highest 16S rRNA gene sequence similarity (93.2 % identity) to Tepidanaerobacter syntrophicus DSM 15584T. The phylogenetic, phenotypic and chemotaxonomic data showed that strain SK-G1T (=CCAM 530T=KCTC 15783T=JCM 33158T) represents a novel species of a new genus Biomaibacteracetigenes gen. nov., sp. nov. The results of phylogenetic and phylogenomic analyses indicated that the genera Biomaibacter, Caldanaerovirga, Fervidicola, Tepidanaerobacter, Thermosediminibacter, Thermovenabulum and Thermovoraxformed a clade with high bootstrap support distinguishing to other taxon within the order Thermoanaerobacterales. This clade is proposed as Thermosediminibacterales ord. nov. and includes Tepidanaerobacteraceae fam. nov. and Thermosediminibacteraceae fam. nov. Emended descriptions of the order Thermoanaerobacterales and family Syntrophomonadaceae are also provided.


Assuntos
Bacilos Gram-Negativos Anaeróbios Retos, Helicoidais e Curvos/classificação , Campos de Petróleo e Gás/microbiologia , Filogenia , Esgotos/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Bacilos Gram-Negativos Anaeróbios Retos, Helicoidais e Curvos/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
5.
J Nat Prod ; 81(1): 98-105, 2018 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-29281282

RESUMO

Concise total syntheses of the natural phytoalexins 2-hydroxy-8-(4-hydroxyphenyl)phenalen-1-one (1), 2-hydroxy-8-(3,4-dihydroxyphenyl)phenalen-1-one (2), and hydroxyanigorufone (4), together with regioisomer 3 are accomplished in 11 or 12 steps. The synthetic strategy features a Friedel-Crafts acylation to construct the 1H-phenalen-1-one tricyclic core followed by a Suzuki cross-coupling to obtain the target compounds.


Assuntos
Fenalenos/química , Sesquiterpenos/química , Acilação , Produtos Biológicos/química , Fitoalexinas
6.
Medicine (Baltimore) ; 95(46): e5366, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27861367

RESUMO

A hypercoagulable state exists in patients with nephrotic syndrome (NS), which more easily leads to venous thromboembolism (VTE). However, whether acute kidney injury (AKI), a common complication of NS, affects the hypercoagulable state and VTE has rarely been elucidated. In this study, we aimed to explore coagulation changes and analyze relevant influencing factors in NS-AKI patients.A total of 269 consecutive NS patients with minimal change disease (MCD) between 2011 and 2016 were included in this observational study. Ninety-one cases were in the AKI group and 178 cases in the non-AKI group. The 1:1 propensity score matching (PSM) method was applied to match the baseline information. The coagulation biomarkers were compared, and the thrombosis events were recorded. Linear correlation was performed to detect any relation between D-dimer and clinical data.The PSM method gave matched pairs of 88 MCD patients with AKI and non-AKI patients, resulting in no differences in baseline information. The D-dimer, fibrinogen, and thromboelastography parameters maximum amplitude (MA), G values of the MCD-AKI patients were significantly higher than the levels of the MCD patients without AKI (D-dimer: 1.8 [1.0, 3.3] vs 1.1 [0.6, 1.7] mg/L, P < 0.001; fibrinogen: 7.0±2.0 vs 6.5 ±â€Š1.4 g/L, P = 0.036; MA: 74.6 ±â€Š5.0 vs 70.5 ±â€Š5.3 mm, P = 0.020; G: 15.7 ±â€Š5.3 vs 12.5 ±â€Š3.3, P = 0.034). For the MCD patients, the serum creatinine, white blood cell count, and interleukin-6 levels in the patients with D-dimers >1 mg/L were significantly higher than those of patients with D-dimers ≤1 mg/L. The correlation analysis showed that the D-dimer level was correlated with serum creatinine, white blood cell count, and interleukin-6 (r = 0.410, P =  < 0.001; r = 0.248, P =  < 0.001; r = 0.306, P =  < 0.001, respectively). Five deep vein thrombosis events occurred in the AKI group and 1 pulmonary embolism event occurred in the non-AKI group after adjusting the propensity score value. AKI appeared to have an association with higher incidence of VTE, but the difference was not statistically significant (RR: 4.9, 95% CI: 0.6-42.7, P = 0.154).The MCD-NS patients complicated with AKI had a more severe hypercoagulable state, which might be associated with the active inflammation of AKI that mediated activation of the coagulation system.


Assuntos
Injúria Renal Aguda/complicações , Transtornos da Coagulação Sanguínea/etiologia , Nefrose Lipoide/complicações , Injúria Renal Aguda/diagnóstico , Adulto , Biomarcadores/sangue , Biópsia , Testes de Coagulação Sanguínea , Feminino , Humanos , Masculino , Nefrose Lipoide/diagnóstico , Pontuação de Propensão , Estudos Retrospectivos , Tromboelastografia
7.
Opt Express ; 23(3): 2879-88, 2015 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-25836149

RESUMO

Thermal and high speed modulation characteristics are investigated for a unidirectional-emission microdisk laser with a radius of 7 µm surrounded by BCB-cladding layer, with a threshold current of 1.5 mA at the temperature of 287 K. The lasing spectra under different widths of pulsed current are measured to characterize the temperature rise during the pulse period, and the thermal distribution in the microdisk laser is simulated by the finite-element modeling technique. A temperature rise of 25 K is estimated for the microdisk laser biased at 20 mA. Furthermore, small signal modulation response with 3dB bandwidth up to 20 GHz is obtained for the microdisk laser at the biasing current of 18 mA, and eye-diagrams at the modulation bit rates of 20, 25, and 30 GHz are also measured at the temperature of 287 K.

8.
Opt Lett ; 38(19): 3807-10, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24081058

RESUMO

A four-wavelength microdisk laser array laterally coupled with a bus waveguide is demonstrated numerically and experimentally. The coupled-mode characteristics as well as scattering loss in the bus waveguide caused by the connected microdisks are simulated by a 2D finite-difference time-domain technique. An AlGaInAs/InP microdisk laser array with circular radii of 10.1, 10.2, 10.3, and 10.4 µm is designed and fabricated by common photolithography and an inductively coupled-plasma etching technique. Continuous-wave electrically injected operation is realized at room temperature with the lowest threshold current of 3 mA. Four-wavelength lasing operation is realized with wavelength intervals of 3-4 nm and side mode suppression ratios larger than 25 dB. Finally, the influences of heating effect and thermal cross talk on lasing mode wavelength tuning are investigated experimentally.

9.
Opt Express ; 21(13): 16069-74, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23842394

RESUMO

Vertical radiation loss and far-field pattern are investigated for microcylinder lasers by 3D FDTD simulation and experimentally. The numerical results show that an output waveguide connected to the microcylinder resonator can result in additional vertical radiation loss for high Q coupled modes and affect the far field pattern. The vertical radiation loss can be controlled by adjusting the up cladding layer thickness. Furthermore, two lobes of vertical far-field patterns are observed for a 15-µm-radius microcylinder laser connected with an output waveguide, which confirms the vertical radiation loss.

10.
Opt Express ; 21(2): 2165-70, 2013 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-23389197

RESUMO

Defected circular resonators laterally confined by a metal layer with a flat side as an emitting window are numerically investigated based on the boundary element method for realizing unidirectional emission microlasers. The results indicate that Fabry-Pérot (FP) modes become high Q confined modes in the defected circular resonator with a metallic layer. The mode coupling between the FP mode and chaotic-like mode can result in high Q confined mode for unidirectional emission with a narrow far field pattern.


Assuntos
Interferometria/instrumentação , Lasers , Lentes , Metais , Refratometria/instrumentação , Transdutores , Desenho de Equipamento , Análise de Falha de Equipamento
11.
Appl Opt ; 51(17): 3930-5, 2012 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-22695672

RESUMO

We demonstrate wide-angle emission and single mode operation in deformed circular microlasers with a flat side. The mode characteristics of a metallic confined deformed circular resonator with a flat side are investigated by finite-difference time-domain simulation. The numerical results indicate that this structure is suitable to realize wide-angle emission. Furthermore, metallic confined deformed circular microlasers with a flat side are fabricated using common photolithography and inductively coupled-plasma etching techniques. A continuous-wave single-mode operation with a side mode suppression ratio of 25 dB is achieved at an injection current of 4 mA for an 8 µm radius microlaser with a flat side. Additionally, wide angle emission over 120° is observed from the far-field pattern.

12.
Opt Lett ; 37(11): 1977-9, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22660093

RESUMO

We experimentally investigate the coherence of a single mode InAlGaAs/InP cylindrical microlaser with two output waveguides. For a cylindrical microlaser with a radius of 15 µm and two 2 µm-wide output waveguides, single mode operation with a side mode suppression ratio of 30 dB is realized, and a far-field interferometric pattern similar to a Young's interferometer is observed. The results indicate that the microlasers with two output waveguides can be used as the light source for an optical sensor by monitoring the phase change of the output emission from one port versus that of the other port.

13.
Opt Lett ; 36(17): 3515-7, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21886262

RESUMO

Optical bistability is realized in GaInAsP/InP coupled-circular resonator microlasers, which are fabricated by planar technology. For a coupled-circular resonator microlaser with the radius of 20 µm and a 2 µm-wide bus waveguide, hysteresis loops are observed for the output power coupling into an optical fiber versus the cw injection current at room temperature. The laser output spectra of the upper and lower states of the hysteresis loop indicate that the bistability is related to mode competitions. The optical bistability can be explained as the mode competition between the symmetry and antisymmetry coupled modes relative to the bus waveguide.

14.
J Exp Bot ; 60(6): 1569-77, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19246592

RESUMO

Proteinases play a critical role in developmental homeostasis and in response to environ-mental stimuli. Our present research reports that a new cysteine protease, NtCP56, is involved in the development of pollen grains in Nicotiana tabacum L. The NtCP56 gene, which encodes a protein of 361 amino acid residues with a calculated molecular mass of 40 kDa, is strongly expressed in anthers. The recombinant NtCP56 showed a high activity towards casein. Kinetic analysis revealed a K(m) of 2.20 mg ml(-1) and V(max) of 11.07 microg ml(-1) min(-1). The recombinant NtCP56 retained more than 50% of its maximum enzymatic activity from 20 degrees C to 60 degrees C with an optimum Tm range of 30-50 degrees C. The enzyme had a maximum activity at approximately pH 6.5. Suppression of the NtCP56 gene in anti-sense transgenic tobaccos resulted in the sterility of pollen grains. Our data indicated that, as a cysteine protease, NtCP56 might play an important role in pollen development.


Assuntos
Cisteína Endopeptidases/metabolismo , Grão Comestível/crescimento & desenvolvimento , Nicotiana/enzimologia , Proteínas de Plantas/metabolismo , Pólen/crescimento & desenvolvimento , Sequência de Aminoácidos , Sequência de Bases , Cisteína Endopeptidases/química , Cisteína Endopeptidases/genética , Grão Comestível/química , Grão Comestível/enzimologia , Grão Comestível/genética , Regulação Enzimológica da Expressão Gênica , Cinética , Dados de Sequência Molecular , Peso Molecular , Proteínas de Plantas/química , Proteínas de Plantas/genética , Pólen/química , Pólen/enzimologia , Pólen/genética , Nicotiana/química , Nicotiana/genética , Nicotiana/crescimento & desenvolvimento
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