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1.
Artigo em Inglês | MEDLINE | ID: mdl-32038002

RESUMO

Two Gram-stain-positive, catalase-positive and oxidase-negative, aerobic, non-motile, cellobiose-utilizing, short-rod-shaped strains (Z28T and Z29) were isolated from faeces of Tibetan antelope (Pantholops hodgsonii) collected on the Qinghai-Tibet Plateau. Strain Z28T shared 98.1, 98.0, 97.8 and 97.4 % 16S rRNA gene similarity, 24.1, 22.8, 23.2 and 26.3 % digital DNA-DNA hybridization relatedness and 80.8, 80.0, 80.7 and 80.9 % average nucleotide identity values with Cellulomonas oligotrophica DSM 24482T, Cellulomonas flavigena DSM 20109T, Cellulomonas iranensis DSM 14785T and Cellulomonas terrae JCM 14899T, respectively. Results from further phylogenetic analyses based on the 16S rRNA gene and 148 core genes indicated that strains Z28T and Z29 were closest to C. oligotrophica DSM 24482T and C. flavigena DSM 20109T, but clearly separated from the currently recognized species of the genus Cellulomonas. The genomic DNA G+C content of strain Z28T was 75.3 mol%. The major cellular fatty acids were anteiso-C15 : 0, anteiso-C15 : 1 A, C16 : 0 and anteiso-C17 : 0. Ribose and mannose were detected as the whole-cell sugars. The major respiratory quinone was MK-9(H4) and ornithine was the diamino acid of the cell wall. The polar lipids present in strain Z28T were phosphatidylethanolamine, five phospholipids, two aminophospholipids, aminolipid and three unidentified lipids. Comparison of phenotypic and phylogenetic features between the two strains and the related organisms revealed that Z28T and Z29 represent a novel species of the genus Cellulomonas, for which the name Cellulomonas shaoxiangyii sp. nov. is proposed. The type strain is Z28T (=CGMCC 1.16477T=DSM 106200T).

2.
Medicine (Baltimore) ; 99(1): e18673, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31895835

RESUMO

The documents on the median effective concentration of local analgesic were many in primiparas during labor analgesia. However, the studies were fewer in multiparas. To explore the analgesic requirements in multiparas during epidural labor analgesia, we investigated the median effective concentration of ropivacaine with 2 µg/mL fentanyl for epidural labor analgesia in multiparas.Sixty-two women were recruited and assigned to the primipara group and multipara group in this prospective study. All the parturients received ropivacaine combined with 2 µg/mL fentanyl for epidural labor analgesia. The concentration of ropivacaine was determined by the up and down method and an initial concentration was set as 0.1% with a 0.01% interval. Effective analgesia was defined as the visual analog scale (VAS) ≤3 within 30 minutes after epidural administration when cervical dilatation is about 2 cm. The median effective concentration of ropivacaine was calculated by the up and down sequential method. The pain intensity was assessed using VAS. Hemodynamic parameters, the labor stages, and neonatal Apgar scores were recorded. Umbilical artery blood was drawn to analyze. The side effects, if any, were also recorded.The median effective concentration of ropivacaine was 0.057% (95% confidence interval [CI], 0.051-0.064%) in primiparas during epidural labor analgesia, and 0.068% (95% CI, 0.063-0.072%) in multiparas during epidural labor analgesia, there was significant difference between the groups (P = .02).This study indicated that the median effective concentration of ropivacaine with fentanyl for epidural labor analgesia was 0.068% (95% CI, 0.063-0.072%) and increased in multiparas compared with the primiparas (www.chictr.org.cn, registration number: ChiCTR-1800016486).


Assuntos
Analgesia Epidural , Analgesia Obstétrica , Anestésicos Locais/administração & dosagem , Paridade , Ropivacaina/administração & dosagem , Adulto , Feminino , Humanos , Gravidez
3.
Artigo em Inglês | MEDLINE | ID: mdl-31829917

RESUMO

Two strains of Gram-stain-positive, aerobic, non-spore-forming, non-motile, rod-shaped bacteria (designated dk512T and dk508) were isolated from the faeces of Tibetan gazelle (Procapra picticaudata) collected from the Qinghai-Tibet Plateau, PR China. The 16S rRNA gene sequences of the strains showed the highest identity to Microbacterium saccharophilum K-1T (98.0 and 97.9 % similarity, respectively). The phylogenetic analysis based on 16S rRNA gene sequences revealed that dk512T and dk508 were members of the genus Microbacterium, and most closely related to strains Microbacterium mitrae M4-8T and Microbacterium hatanonis FCC-01T. The strains grew optimally on brain-heart infusion (BHI) agar with 5.0 % (v/v) sheep blood at 30 °C, pH 7.0 and with 1.0 % (w/v) NaCl. The genome of type strain dk512T was 3.8 Mb with a G+C content of 70.6 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strain dk512T and previously characterized Microbacterium species were <95 and <70 %, respectively. In strain dk512T, the detected primary cellular fatty acids were anteiso-C15 : 0 and anteiso-C17 : 0, the main respiratory quinones were MK-9 (37.9 %) and MK-10 (35.7 %), and the polar lipids included diphosphatidylglycerol, phosphatidylglycerol and three unidentified glycolipids. The major cell-wall sugars were rhamnose, ribose and galactose. Alanine, glutamic acid, glycine and ornithine were in the cell-wall peptidoglycan. Based on phenotypic data and phylogenetic inference, these two strains represent a novel species of the genus Microbacterium, named here as Microbacterium wangchenii sp. nov, where dk512T is designated the type strain (=CGMCC 1.16590T=JCM 33494T=KCTC 49313T).

4.
Huan Jing Ke Xue ; 40(10): 4513-4522, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854819

RESUMO

Dianshan Lake, a subtropical shallow lake, is the largest freshwater body located in Shanghai. To reveal the temporal and spatial variation of zooplankton community structure and its relationships with environmental factors, monthly data of zooplankton and phytoplankton content and associated physicochemical parameters for 2017 were analyzed using multivariate regression trees (MRT) and principal coordinates analysis (PCoA). The results indicated that there were significant seasonal differences in the community structure of zooplankton (P<0.05). However, spatial variations were significant only in spring and summer (P<0.05). The results indicated that water temperature (WT), chlorophyll-a (Chla), ammonia nitrogen, and cyanobacteria were the key driving factors in the observed spatial and temporal variations in the zooplankton community structure. The MRT analysis illustrated that zooplankton community structure varied strongly across four groups, including spring (13.07℃ ≤ WT<19.57℃), summer (WT ≥ 19.57℃, Chla ≥ 9.03 µg·L-1), autumn (WT ≥ 19.57℃, Chla<9.03 µg·L-1), and winter (WT<13.07℃). In addition, three distinct regions were identified by the cluster analysis. The MRT analysis illustrated that the zooplankton community structure was distinct between samples with relatively lower (<1.11 mg·L-1) and higher concentrations (≥ 1.11 mg·L-1) of ammonia nitrogen in spring. Furthermore, cyanobacteria were identified as a major stressor on zooplankton in summer. These observations further show that that zooplankton community structure in area I (with a cyanobacterial biomass of ≥ 2.58 mg·L-1) was significantly different from other regions (with a cyanobacterial biomass of <2.58 mg·L-1).


Assuntos
Cianobactérias , Zooplâncton , Animais , China , Monitoramento Ambiental , Lagos , Fitoplâncton , Estações do Ano
5.
Environ Sci Technol ; 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31774261

RESUMO

The exhaust gas contains harmful products, including fuel-additive elements such as compounds of sodium, which cause dramatic catalyst deactivation of catalysts during selective catalytic reduction (SCR) of NO with NH3. There is an increasing demand to synthesize alkali-poisoning-resistant catalysts for industrial NH3-SCR applications. In this study, the as-synthesized Fe2O3/MoO3/TiO2 exhibits a high degree of resistance toward Na2SO4 poisoning during the NH3-SCR reaction. With 500 µmol g-1 Na+ poisoning, Fe2O3/MoO3/TiO2 showed approximately 95% (or more) of its original activity throughout the entire temperature rage. Even with 700 µmol g-1 Na+ poisoning, Fe2O3/MoO3/TiO2 still performed well. The 500 and 700 µmol g-1 Na+ loadings dictate that, on average, SCR catalysts could be exposed to alkali-rich and highly dusty environments for more than 14 000 and 20 000 h, respectively. The layered MoO3 building block is used as a binding buffer and sandwiched between the active phase and TiO2 support to provide sufficiently stable binding sites for Na2SO4 poison and to present alkali blocking of the surface active phase. Our findings provide useful information regarding the use of MoO3 as a safety buffer for developing functional NH3-SCR catalysts with enhanced alkali-poisoning-resistant performance and long lifetimes.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31674893

RESUMO

Two strains, designated 2251T and 3058, that were aerobic, Gram-stain-negative, non-motile, coccoid or short rod-shaped bacilli, have recently been isolated from Tibetan antelopes on the Qinghai-Tibet Plateau. The results of phylogenetic analyses of 16S rRNA gene sequences indicated that strains 2251T and 3058 represent a new species within the genus Paracoccus and are most similar to 'Paracoccus gahaiensis' CUG00006T (98.9 and 99.3 %), Paracoccus nototheniae I-41R45T (98.3 and 98.7 %) and Paracoccus hibiscisoli THG-T2.31T (97.6 and 97.8 %). Results of genomic sequence-based phylogenomic analysis agreed with those from 16S rRNA gene sequence analysis. Optimal growth was achieved at pH 7.0-7.5 and 28 °C with marine medium. Cells contained C18 : 1 ω7c as the major cellular fatty acid and ubiquinone-10 as the predominant menaquinone. The polar lipids comprised phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phospholipid, glycolipid and an unidentified lipid. The cell-wall peptidoglycan amino acids were meso-2,6-diaminopimelic acid, alanine and glutamic acid; the major cell-wall sugar was galactose. The G+C content of strain 2251T was 66.5 mol%. Both strains (2251T and 3058) had DNA-DNA relatedness values less than 50 % with all available genomes of the genus Paracoccus in the ncbi database. Differential genotypic inferences, together with phenotypic and biochemical characteristics, demonstrated that strains 2251T and 3058 should be classified as a novel species of the genus Paracoccus, for which the name Paracoccus liaowanqingii sp. nov. is suggested. The type strain is 2251T (=CGMCC 1.16490T=DSM 106269T).

7.
Artigo em Inglês | MEDLINE | ID: mdl-31613742

RESUMO

Two previously undescribed, Gram-stain-positive, rod-shaped strains, 410T and 553, were isolated from faeces of the Tibetan antelope (Pantholops hodgsonii) from the Tibet-Qinghai Plateau, PR China. The optimum growth conditions of the two novel strains were 1 % (w/v) NaCl, 37 °C and pH 7. The end products from glucose fermentation included ethanol and lactic acid. Based on results of 16S rRNA gene sequence comparison and phylogenetic and phylogenomic analyses, strains 410T and 553 were classified into the genus Actinomyces, and were closely related to Actinomyces ruminicola (97.6 %), Actinomyces oricola (93.5 %) and Actinomyces dentalis (90.8 %). The genomic G+C content of strain 410T was 67.4 mol%. Digital DNA-DNA hybridization values between strain 410T and each of the closely related species were under 70 %. The respiratory quinones were MK-10 (68 %) and MK-9 (32 %). The main cellular fatty acids of the isolates were C16 : 0, followed by C18 : 1 ω9c. The major polar lipids were diphosphatidylglycerol and phosphatidylinositol-mannoside. The whole-cell sugars contained rhamnose, ribose and glucose. The diagnostic amino acids of cell-wall peptidoglycan included alanine, glutamic acid, lysine and ornithine. The results of biochemical, chemotaxonomic and genotypic analyses revealed that the two novel strains represent a novel species of genus Actinomyces, for which the name Actinomyces qiguomingii sp. nov. is proposed. The type strain is 410T (=CGMCC 1.16361T= DSM 106201T).

8.
ACS Appl Mater Interfaces ; 11(39): 35888-35895, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31544456

RESUMO

In this work, a novel vertical quantum-dot light-emitting transistor (VQLET) based on a vertical organic thin-film transistor is successfully fabricated. Benefiting from the new vertical architecture, the VQLET is able to afford an extremely high current density, which allows most of the organic thin film transistors (OTFT) even with low mobility (for instance, poly(3-hexylthiophene)) to drive a quantum-dot light-emitting diode (QLED), which was previously unavailable. Moreover, the hole injection barrier could be modulated by the additional gate electrode, which precisely optimizes the charge balance in the device, a critical issue in QLED, resulting in the precise control of current density and brightness of the VQLET. The VQLET shows a high performance with a maximum current efficiency of 37 cd/A. Furthermore, integrating OTFT and QLED into a single device, the VQLET features drastic advantages by realizing active matrix quantum-dot light-emitting diodes (AMQLEDs), which significantly reduces the number of transistors and frees the large area fraction occupied by transistors. Hence, these results indicate that the VQLET provides a new strategy for realizing a low-cost, solution-processed, high-performance OTFT-AMQLED for the flat panel display technology. Moreover, the novel design offers a unique method to exquisitely control the charge balance and maximize the efficiency the QLED.

9.
Int J Syst Evol Microbiol ; 69(11): 3485-3491, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31460856

RESUMO

Two novel, Gram-stain-positive, non-motile, facultatively anaerobic, rod-shaped bacteria (strains 2129T and 2119) were isolated from the faeces of Tibetan antelopes (Pantholops hodgsonii) on the Qinghai-Tibet Plateau, PR China. The 16S rRNA gene sequences of the strains showed highest similarity values to Actinomyces timonensis DSM 23838T (92.9 and 92.8 %, respectively), and phylogenetic analysis based on 16S rRNA gene and genomic sequences indicated that strains 2129T and 2119 represent a new lineage. Strains 2129T and 2119 could ferment d-adonitol and d-xylose, but were unable to utilize d-mannose and d-melibiose nor produce esterase (C4) and proline arylamidase. The G+C contents of the two strains were both 69.0 mol%. Their genomes exhibited less than 40.4 % relatedness in DNA-DNA hybridization tests (below 70 % as the recommended threshold for new species) with all available genomes of the genus Actinomyces in the NCBI database. The major fatty acids of the two strains were C18 : 1ω9c and C16 : 0, and the major polar lipids were diphosphatidylglycerol, glycolipid, phosphatidylinositol, phosphatidyl inositol mannoside and phosphoglycolipid. Based on the results of genotypic, phenotypic and biochemical analyses, it is proposed that the two unidentified bacteria be classified as representing a novel species, Actinomyces lilanjuaniae sp. nov. The type strain is 2129T (=CGMCC 4.7483T=DSM 106426T).


Assuntos
Actinomyces/classificação , Antílopes/microbiologia , Filogenia , Actinomyces/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet
10.
Langmuir ; 35(48): 16037-16042, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31373817

RESUMO

The essential characteristic of the self-propelled jumping droplet is the jumping velocity, which determines its application value in heat transfer enhancement, antifrosting, self-cleaning, and so on. The jumping velocity is directly related to the energy conversion efficiency (i.e., the ratio of jumping kinetic energy surface energy released by coalescence to surface energy released by coalescence) and it is affected by the initial state of droplets but there is no unified theory to describe the relationship between the initial state of droplets and the energy conversion efficiency. In this paper, the projection of the initial chemical potential and the final chemical potential difference of droplets in the direction of jumping is defined as jumping potential by theoretical analysis of the chemical potential evolution. The effects of droplet number, distribution, and radius ratio on energy conversion efficiency can be synthetically characterized by jumping potential. The larger the jumping potential is, the higher the energy conversion efficiency is. Finally, the rationality and universality of the jumping potential are verified by numerical simulations and comparison with previous studies. The jumping potential can explain phenomena that cannot be explained in previous studies and can provide a synthesis critical value of droplet jumping.

11.
Nan Fang Yi Ke Da Xue Xue Bao ; 39(7): 766-771, 2019 Jul 30.
Artigo em Chinês | MEDLINE | ID: mdl-31340907

RESUMO

OBJECTIVE: To explore the causes of oocyte vitrification and its application in assisted reproduction. METHODS: We retrospectively analyzed the data of 26 patients with 27 cycles of oocyte vitrification cryopreservation undergoing intracytoplasmic sperm injection (ICSI) and embryo transfer between January, 2008 and October, 2018. The causes of oocyte vitrification and the outcomes of ICSI and clinical pregnancy were analyzed. RESULTS: The causes of oocytes vitrification included mainly azoospermia or severe spermatogenesis disorder of the husband, failure to obtain sperms from the husband, failure of the husband to be present on the day of oocyte retrieval and acute diseases of the husband to not allow sperm collection. A total of 274 oocytes were frozen in 27 oocyte retrieval cycles, and 217 eggs were thawed in 19 cycles with a survival rate of 81.11% (176/217). The normal fertilization rate, cleavage rate and high-quality embryo rate was 74.81% (98/131), 89.80% (88/98) and 36.73% (36/98), respectively. Fifteen patients underwent embryo transfer, and the clinical pregnancy rate and live birth rate was 53.33% (8/15) and 33.33% (5/15), respectively. Compared with patients below 35 years of age, the patients aged above 35 years had significantly lower oocyte survival rate after thawing (82.76% vs 74.42%, P=0.211), clinical pregnancy rate (77.78% vs 16.67%, P=0.041) and live birth rate (55.56% vs 0, P=0.044). CONCLUSIONS: Oocytes vitrification can be used as a remedy for infertile couples who fail to provide sperms due to male factors on the day of oocyte retrieval. Vitrification of the oocytes does not significantly affect the fertilization rate or the clinical pregnancy rate. The survival rate of the thawed oocytes is related to the age of the wife, and an age younger than 35 years can be optimal for achieving favorable clinical pregnancy outcomes after oocyte vitrification.


Assuntos
Oócitos , Vitrificação , Adulto , Criopreservação , Transferência Embrionária , Feminino , Humanos , Masculino , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
12.
Int J Syst Evol Microbiol ; 69(9): 2942-2947, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31334694

RESUMO

Two hitherto unknown bacteria (strains 313T and 352) were recovered from the faeces of Tibetan antelopes on the Tibet-Qinghai Plateau, PR China. Cells were rod-shaped and Gram-stain-positive. The optimal growth conditions were at 37 °C and pH 7. The isolates were closely related to Actinotignum sanguinis (92.6 % 16S rRNA gene sequence similarity), Arcanobacterium haemolyticum (92.5 %), Actinotignum schaalii (92.4 %), Actinobaculum massiliense (92.2 %) and Flaviflexus huanghaiensis (91.6 %). Phylogenetic analyses showed that strains 313T and 352 clustered independently in the vicinity of the genera Actinotignum, Actinobaculum and Flaviflexus, but could not be classified clearly as a member of any of these genera. Phylogenomic analysis also indicated that strains 313T and 352 formed an independent branch in the family Actinomycetaceae. The major cellular fatty acids of the strains were C16 : 0 and C18 : 1ω9c. The polar lipids comprised diphosphatidylglycerol, phosphatidylinositol mannoside, phosphatidylglycerol, phosphatidylinositol and five unidentified components. The peptidoglycan contained lysine, alanine and glutamic acid. The respiratory quinone was absent. The whole-cell sugars included glucose and rhamnose. The DNA G+C content of strain 313T was 60.6 mol%. Based on the low 16S rRNA gene sequence similarities, its taxonomic position in the phylogenetic and phylogenomic trees and its unique lipid pattern, we propose that strains 313T and 352 represent members of a novel species in a new genus, for which the name Fudania jinshanensis gen. nov., sp. nov. is proposed. The type strain is 313T (=CGMCC 4.7453T=DSM 106216T).


Assuntos
Actinomycetaceae/classificação , Antílopes/microbiologia , Filogenia , Actinomycetaceae/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet
13.
Acta Biochim Biophys Sin (Shanghai) ; 51(8): 791-798, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31294443

RESUMO

MicroRNAs (miRNAs) are a class of endogenous noncoding genes that regulate gene expression at the posttranscriptional level. In recent decades, miRNAs have been reported to play important roles in tumor growth and metastasis, while some reported functions of a specific miRNA in tumorigenesis are contradictory. In this study, we reevaluated the role of miR-214, which has been reported to serve as an oncogene or anti-oncogene in breast cancer metastasis. We found that miR-214 inhibited breast cancer via targeting RNF8, a newly identified regulator that could promote epithelial-mesenchymal transition (EMT). Specifically, the survival rate of breast cancer patients was positively correlated with miR-214 levels and negatively correlated with RNF8 expression. The overexpression of miR-214 inhibited cell proliferation and invasion of breast cancer, while suppression of miR-214 by chemically modified antagomir enhanced the proliferation and invasion of breast cancer cells. Furthermore, miR-214 could modulate the EMT process via downregulating RNF8. To our knowledge, this is the first report that reveals the role of the miR-214-RNF8 axis in EMT, and our results demonstrate a novel mechanism for miR-214 acting as a tumor suppressor through the regulation of EMT.

14.
ACS Appl Mater Interfaces ; 11(22): 20214-20224, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31074275

RESUMO

The identifying characteristic of an organic electrochemical transistor (OECT) is the coupling between ionic and electronic charges within the entire volume of the channel. In this work, by taking advantage of the volumetric nature of the OECTs' response, a novel flexible photodetector is reported for the first time based on all-solid-state OECT with an excellent responsivity of up to 6.7 × 106 A/W, detectivity as high as 3.6 × 1013 Jones, and a fast response of ∼0.13 s in the visible range, which are superior to those of the majority of the reported organic phototransistors (OPTs) based on field-effect transistors (FETs) and even better than those of FET-based phototransistors with two-dimensional (MoS2 and graphene) and perovskite materials. The high performance of the devices was ascribed to the combination of the higher carrier mobility of poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonate) (PEDOT:PSS) as a channel and the volumetric nature of the OECTs' response, and the charge density of the volumetric channel was efficiently modulated by incident light compared to FETs. Moreover, OECT-based OPTs with quantum dots (CdSe/ZnS) as a light sensitizer were characterized under ultraviolet light, and they exhibited excellent photosensitivity, which further verified the superiority of OECT for phototransistors. Furthermore, a flexible image sensor was fabricated for the first time by integrating flexible OECTs-OPTs into a 10 × 10 array, which can clearly identify the target image under a bending state, indicating the great potential of OECTs-OPTs in the application of low-power, ultrasensitive flexible photodetectors and imaging technology.

15.
Int J Syst Evol Microbiol ; 69(10): 2979-2986, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31145678

RESUMO

Two Gram-stain-negative, catalase- and oxidase-positive, non-spore-forming, aerobic, motile, flagellated, and coccus-shaped strains (Z23T and Z24) were isolated from faeces of Tibetan antelopes (Pantholops hodgsonii) on the Qinghai-Tibet Plateau, PR China. Results of the morphological, biochemical, and phylogenetic studies indicated that they were similar to each other, but distinct from existing species of the genus Roseomonas. The proposed type strain, Z23T, had 97.8, 97.1 and 96.8 % 16S rRNA similarity to Roseomonas ludipueritiae DSM 14915T, Roseomonas aerofrigidensis JCM 31878T and Roseomonas aerophila KACC 16529T. Results from further phylogenetic analyses based on the 16S rRNA gene and 857 core genes indicated that the two strains were members of Roseomonas, but clearly separated from the currently recognized species. Strains Z23T had 43.8 %, 25.0 % DNA-DNA relatedness and 91.2, 81.3 % ANI values with R. ludipueritiae DSM 14915T and R. aerophila KACC 16529T. The genomic DNA G+C content of strain Z23T was 68.6 mol%. The major cellular fatty acids of strain Z23T were C18 : 1ω7c and/or C18 : 1ω6c and C19 : 0cyclo ω8c. The cell-wall sugars included glucose, rhamnose and ribose. Q-10 was the sole respiratory quinone, and spermidine was the major polyamine component. Polar lipids present in strain Z23T were phosphatidylcholine, diphosphatidylglycerol, phosphatidylethanolamine, aminophospholipid, phosphatidylglycerol, three aminolipids, two phospholipids and two unidentified lipids. Based on the distinct differences from other Roseomonas species judged from the genotypic and phenotypic data, a novel species represented by Z23T and Z24, Roseomonas wenyumeiae sp. nov., is proposed. The type strain is Z23T (=CGMCC 1.16540T=DSM 106207T).


Assuntos
Antílopes/microbiologia , Methylobacteriaceae/classificação , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Methylobacteriaceae/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
16.
Environ Sci Technol ; 53(9): 5309-5318, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30964662

RESUMO

Surface restructuring is a useful approach to modulating the properties of nanoparticles. A low-dimensional atomic-thickness active species may exhibit remarkably enhanced activity, in contrast to the inert nature of its bulk counterparts. Here, we report a procedure for growing in situ a low-dimensional monolayer-thick MoO3 entity from its bulk precursor. Traditional analysis of NO abatement catalyzed by vanadium-based materials implicates vanadium as the active site enhanced by the promoter element W or Mo. However, we report here that the atomic-thickness MoO3 film can function alone as an efficient NO abatement catalyst by itself; to achieve comparable performance with the industrial catalysts, it is not necessary to add vanadium oxide, which often has serious toxicity issues associated with it. We find that submonolayer MoO3 is responsible for the observed high activity. Electron microscopy and Raman spectroscopy reveal that the monolayer-thick MoO3 surface phase is directly attached to the anatase TiO2 support. The ab initio quantum calculations predict that the bidimensional MoO3 surface phase would provide more electron back-donation to the antibonding orbital of reactants and thus more efficient reactant activation. The spectral evolution of in situ DRIFTS indicates that the redox mechanism over the low-dimensional MoO3/TiO2 involves both Brønsted and Lewis acid sites during the reaction cycle.


Assuntos
Óxido Nítrico , Óxidos de Nitrogênio , Catálise , Óxidos , Vanádio
17.
Int J Syst Evol Microbiol ; 69(5): 1426-1432, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30860460

RESUMO

Two rod-shaped, slightly halophilic and extremely halotolerant bacterial strains (X-1125T and X-1174), which were Gram-stain-positive, facultatively anaerobic and motile with peritrichous flagella, were isolated from the faeces of Tibetan antelopes. Their optimal temperature, NaCl concentration and pH for growth were 28 °C, 3 % (w/v) NaCl and pH 7.5, respectively. Based on the results of 16S rRNA gene sequences, and phylogenetic and phylogenomic analyses, their nearest phylogenetic neighbours were Paraliobacillussediminis KCTC 33762T (98.4 % similarity), Paraliobacillusquinghaiensis CGMCC 1.6333T (96.9 %) and Paraliobacillusryukyuensis NBRC 100001T (95.9 %) while the 16S rRNA genes of strains X-1125T and X-1174 were highly similar (99.7 %) to each other. The polar lipids comprised diphosphatidylglycerol, two unidentified phospholipids and four unidentified lipids. MK-7 was the sole menaquinone (100 %). The cell wall contained alanine, glycine, glutamic acid and meso-diaminopimelic acid. The major fatty acids (>9 %) were anteiso-C15 : 0, anteiso-C17 : 0 and C16 : 1ω11c. The in silico DNA-DNA hybridization value between strains X-1125T and X-1174 was 97.8 % (well above the species threshold), but their values were lower than the 70 % threshold with the three closely related type strains. Strains X-1125T and X-1174 had DNA G+C contents (mol%) of 35.2 and 35.1 %, respectively. Based on the presented data, strains X-1125T and X-1174 hereby represent a novel species of the genus Paraliobacillus, for which the name Paraliobacillus zengyii sp. nov. is proposed. The type strain is X-1125T (=DSM 107811T=CGMCC 1.16464T).


Assuntos
Antílopes/microbiologia , Bacillaceae/classificação , Filogenia , Animais , Bacillaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Fezes/microbiologia , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet , Vitamina K 2/análogos & derivados , Vitamina K 2/química
18.
J Biotechnol ; 296: 69-74, 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-30885657

RESUMO

Synthetic scaffold systems, which exhibit enzyme clustering effect, have been considered as an important parallel approach for metabolic flux control and pathway enhancement. Here, we described an improved DNA-based scaffold system for synthetic tri-enzymatic pathway in Escherichia coli. With plasmid DNA serving as scaffold and exogenous enzymes fused with rationally designed transcription activator-like effectors (TALEs), our approach successfully clustered three TALE-fused enzymes and significantly increased the production of a mevalonate-producing tri-enzymatic pathway with the optimized scaffold structure and plasmid copy number. These results further suggested the scalability and robustness of the TALE-based scaffold system, and we can assume that it can be used on numerous multi-enzyme metabolic pathways due to its programmable features.


Assuntos
DNA/genética , Engenharia Metabólica , Redes e Vias Metabólicas/genética , Efetores Semelhantes a Ativadores de Transcrição/química , DNA/química , Escherichia coli/genética , Ácido Mevalônico/química , Ácido Mevalônico/metabolismo , Plasmídeos/genética , Efetores Semelhantes a Ativadores de Transcrição/genética
19.
Int J Syst Evol Microbiol ; 69(4): 1093-1098, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30747615

RESUMO

Two novel aerobic, Gram-staining-positive and non-spore-forming bacterial strains, 194T and S1194, were isolated from faeces of Tibetan antelopes sampled at the Qinghai-Tibet Plateau of China. The strains were able to grow in medium up to 10 % NaCl, similar to the NaCl-resistant property of the genus Salinibacterium members. The 16S rRNA gene sequences of the strains showed the highest similarity to Salinibacterium xinjiangense(98.1-98.2 %), and phylogenetic analysis based on 16S rRNA gene sequences indicated that strains 194T and S1194 represent a new lineage. The DNA G+C contents of strain 194T and S1194 are 64.1 and 64.2 mol%. Their genomes exhibit less than 96 % average nucleotide identity and 70 % DNA-DNA relatedness to known species of Salinibacterium. Strains 194T and S1194 are unable to utilize d-mannose or produce naphthol-AS-BI-phosphohydrolase. The two strains had anteiso-C15 : 0 and anteiso-C17 : 0 as major fatty acids, and their cell walls contained lysine, alanine, glycine and glutamic acid. The predominant menaquinones identified were MK-11 and MK-10, with diphosphatidylglycerol and phosphatidylglycerol as major polar lipids. Overall, the major cellular content profiles of 194T agreed with those of Salinibacterium xinjiangense and Salinibacterium amurskyense, though the proportions were distinct. Based on genotypic, phenotypic and biochemical analyses, the novel species Salinibacterium hongtaonis sp. nov. is proposed. The type strain is 194T (=CGMCC 1.16371T=DSM 106171T).


Assuntos
Actinobacteria/classificação , Antílopes/microbiologia , Filogenia , Actinobacteria/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano , Ácidos Graxos , Fezes/microbiologia , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet , Vitamina K 2/química
20.
Int J Syst Evol Microbiol ; 69(4): 1117-1122, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30762515

RESUMO

Strains 449T and 622 are both aerobic, Gram-stain-positive, short, rod-shaped bacilli that were recently isolated from the faeces of Tibetan antelopes on the Qinghai-Tibet Plateau in China. Their 16S rRNA gene sequences were most similar to those of Mycetocola zhadangensis ZD1-4T(97.9-98.0 %) and Mycetocola miduiensis CGMCC 1.11101T(97.3-97.4 %). Phylogenetic analysis of the 16S rRNA gene sequences further suggested that strains 449T and 622 represent a new lineage within the genus Mycetocola. The G+C content of strain 449T is 64.9 mol%. Optimal growth was achieved at pH 7.0 and 28 °C. Cells contained anteiso-C15 : 0 as the major cellular fatty acid, MK-10 and MK-11 as predominant menaquinones, diphosphatidylglycerol and phosphatidylglycerol as major polar lipids, and lysine as the diagnostic diamino acid. The DNA-DNA hybridization values of strains 449T and 622 were below the 70 % cut-off with respect to known strains of the genus Mycetocola. Based on these genotypic, phenotypic and biochemical characteristics, it seems rational to conclude that strains 449T and 622 belong to the genus Mycetocola and thus represent a novel species, for which the name Mycetocola zhujimingii sp. nov. is proposed. The type strain is 449T (=CGMCC 1.16372T=DSM 106173T).


Assuntos
Actinobacteria/classificação , Antílopes/microbiologia , Filogenia , Actinobacteria/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet , Vitamina K 2/química
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