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1.
Artigo em Inglês | MEDLINE | ID: mdl-38334269

RESUMO

A novel Gram-positive strain WQ 127069T that was isolated from the soil of Baima Snow Mountain, a habitat of highly endangered Yunnan snub-nosed monkeys (Rhinopithecus bieti), was subjected to a polyphasic taxonomic study. Phylogenetic analysis based on the 16S rRNA gene sequences showed that the isolate belongs to the genus Paenibacillus, showing 98.4 and 96.08 % sequence similarity to the type strains Paenibacillus periandrae PM10T and Paenibacillus foliorum LMG 31456T, respectively. The G+C content of the genomic DNA of strain WQ127069T was 45.6 mol%. The predominant isoprenoid quinone was MK-7, and meso-diaminopimelic acid was present in peptidoglycan. The major cellular fatty acids were antiiso-C15 : 0, iso-C15 : 0 and C16 : 0. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and phosphatidylmonomethylethanolamine. The whole genome average nucleotide identity and digital DNA-DNA hybridization values between strain WQ 127069T and strain PM10T were 93.2 and 52.5 %, respectively. Growth occurred at 5-40 °C (optimally at 20-35 °C), pH 6-8 (optimally at pH7.0) and with 0.5-2 % (w/v) NaCl (optimally at 0.5 %). On the basis of the taxonomic evidence, a novel species, Paenibacillus baimaensis sp. nov., is proposed. The type strain is WQ 127069T (=KCTC 43480T=CCTCC AB 2022381T).


Assuntos
Paenibacillus , Presbytini , Animais , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Solo , DNA Bacteriano/genética , Composição de Bases , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , China , Ecossistema
2.
J Am Chem Soc ; 144(19): 8676-8682, 2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35507412

RESUMO

Artificial photocatalytic CO2 reduction, using water as the reductant, is challenging mainly because it is difficult for multiple functional units to cooperate efficiently. Here, we show that the classic photosensitive and H2O-oxidizing ruthenium bipyridyl units and CO2-reducing cobalt imidazolate units can be incorporated into a metal-organic framework using a classic organic ligand, imidazo[4,5-f][1,10]phenanthroline. Under visible light without additional sacrificial agents and photosensitizers, the overall conversion of CO2 and H2O to CO and O2 was achieved by the multifunctional photocatalyst in the CH3CN/H2O mixed solvent with a high CO production rate of 11.2 µmol g-1 h-1 and CO selectivity of ca. 100%. Thanks to its ultramicroporous structure with moderately strong CO2 adsorption ability, the photocatalyst also exhibited high performances with CO/CH4 production rates of 5.15/0.62 and 4.26/0.20 µmol g-1 h-1 in the gas phase with pure and even diluted CO2, respectively. Photoluminescence emission spectroscopy and photoelectrochemical tests confirmed that the photosensitive and catalytic units cooperated well to give suitable photocatalytic redox potentials and fast electron-hole separation.


Assuntos
Estruturas Metalorgânicas , Rutênio , 2,2'-Dipiridil , Dióxido de Carbono/química , Cobalto/química , Estruturas Metalorgânicas/química , Rutênio/química
3.
Curr Microbiol ; 79(3): 92, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35129696

RESUMO

A novel bacterium designated WQ 366 T was isolated from the faeces of Bos taurus, foraging on the slopes of the Baima Snow Mountain in Yunnan, China. The isolate grew optimally at 30 â„ƒ and pH 7.0-8.0 without NaCl. The cells were Gram-stain-negative, aerobic, rod-shaped, non-gliding, catalase-positive, and produced yellow color colonies on Columbia Agar. A polyphasic study was applied to clarify its taxonomic position through 16S rRNA gene and genome sequence analysis, and other extensive biological typing. Phylogenetic analysis revealed that the isolate was affiliated to the genus Sphingobacterium and its 16S rRNA gene sequence was closely related to Sphingobacterium bovisgrunnientis YK2 T (97.3%), Sphingobacterium composti T5-12 T (96.4%), and Sphingobacterium cavernae 5.0403-2 T (96.4%). The calculated whole genome average nucleotide identity (ANI) and the digital DNA-DNA hybridization values between strain WQ 366 T and the three related strains were 78.3, 78.6, 73.9 and 21.2, 21.2, 21.0%, respectively. The predominant fatty acids (>10%) were iso-C15:0, iso-C17:0 3-OH, Summed Feature 3 (C16:1 ω7c and/or C16:1 ω6c), and Summed feature 9 (iso-C17:1 ω9c and 10-methyl C16:0). The main polar lipids were PE, GPL, GL, and PL. MK-7 was the major menaquinone. The genome size and the G + C content of WQ 366 T was 4.1 Mb and 34.6%, respectively. All these results indicated that strain WQ 366 T represents a novel species of the Sphingobacterium genus. Therefore, the name Sphingobacterium bovistauri sp. nov. is proposed, and the type strain is WQ 366 T (= CCTCC AA 2020029 T = KCTC 82395 T).


Assuntos
Sphingobacterium , Animais , Técnicas de Tipagem Bacteriana , Bovinos , China , DNA Bacteriano/genética , Ácidos Graxos , Fezes , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sphingobacterium/genética , Vitamina K 2
4.
Arch Microbiol ; 203(7): 4629-4634, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34165622

RESUMO

A novel bacterium, WQ 047T, was isolated from the faeces of Rhinopithecus bieti, a highly endangered primate endemic to China. The cells were aerobic, oval/rod-shaped, Gram-stain-negative, non-motile, catalase positive, and produced yellow pigmented colonies on Columbia Agar. The taxonomic position of WQ 047T was clarified by applying a polyphasic study based on 16S rRNA gene sequence phylogenetic analysis, extensive biological typing, and whole genome sequencing. Phylogenetic analysis indicated that stain WQ 047T belonged to the genus Sphingobacterium and its 16S rRNA gene sequence exhibited 96.47% pairwise similarity with that of the closest relatives Sphingobacterium nematocida M-SX103T. The calculated whole genome average nucleotide identity (ANI) value between strain WQ 047T and strain M-SX103 was 72.3%. The digital DNA-DNA hybridization value of strain WQ 047T and M-SX103T was 15.73%, which was obtained by calculating the genome-to-genome distance. The major fatty acids were C15:0 iso, C17:0 iso 3-OH, Summed Feature 3 (C16:1 ω7c/C16:1 ω6c) and Summed feature 9 (iso-C17:1ω9c and/or 10-methyl C16:0). The predominant polar lipids were PE, PL and APL. MK-7 was the predominant menaquinone. The G + C content of WQ 047T was 34.89 mol% according to genome analysis. All these characteristics were consistent with those of the genus of Sphingobacterium. Therefore, based on these results, we propose a novel species for which the name Sphingobacterium rhinopitheci sp. Nov. is proposed, with the type strain WQ 047T (= CCTCC AA 2020026T = KCTC82393T).


Assuntos
Presbytini , Sphingobacterium , Animais , China , Ácidos Graxos/análise , Fezes/microbiologia , Filogenia , Presbytini/microbiologia , RNA Ribossômico 16S/genética , Especificidade da Espécie , Sphingobacterium/classificação , Sphingobacterium/genética
5.
Artigo em Inglês | MEDLINE | ID: mdl-34382925

RESUMO

A novel Gram-stain-negative strain, WQ 117T, isolated from the faeces of Rhinopithecus bieti collected at Yunnan Snub-nosed Monkey National Park, Yunnan province, PR China, was subjected to a polyphasic taxonomic study. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate represented a member of the genus Faecalibacter, sharing 97.64 % sequence similarity with the type strain Faecalibacter macacae YIM 102668T. The G+C content of the genomic DNA of WQ117T was 30.5 mol%. The predominant isoprenoid quinone was MK-6. The major cellular fatty acids was iso-C15 : 0. The whole genome average nucleotide identity (gANI) values and the digital DNA-DNA hybridization values between WQ 117T and YIM 102668T were 79.66 % and 22.20 %, respectively. Growth occurred at 0-50 °C (optimally at 28-35 °C), pH 7.0-9.0 (optimally at pH 8.0) and with 0-2 % (w/v) NaCl (optimally without NaCl). On the basis of the taxonomic evidence, a novel species, Faecalibacter rhinopitheci sp. nov., is proposed. The type strain is WQ 117T (=KCTC 82394T=CCTCC AA 2020027T).


Assuntos
Bacteroidetes/classificação , Filogenia , Presbytini , Animais , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Hibridização de Ácido Nucleico , Presbytini/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
6.
J Am Chem Soc ; 140(1): 38-41, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29258308

RESUMO

Converting CO2 into fuels via photochemical reactions relies on highly efficient and selective catalysts. We demonstrate that the catalytic active metal center can cooperate with neighboring hydroxide ligands to boost the photocatalytic CO2 reduction. Six cobalt-based metal-organic frameworks (MOFs) with different coordination environments are studied at the same reaction condition (photosensitizer, electron donor, water/organic mixed solvent, and visible light). In pure CO2 at 1.0 atm, the MOFs bearing µ-OH- ligands neighboring the open Co centers showed CO selectivities and turnover frequencies (TOFs) up to 98.2% and 0.059 s-1, respectively. More importantly, their TOFs reduced only ca. 20% when the CO2 partial pressure was reduced to 0.1 atm, while other MOFs reduced by at least 90%. Periodic density functional theory calculations and isotope tracing experiments showed that the µ-OH- ligands serve not only as strong hydrogen-bonding donors to stabilize the initial Co-CO2 adduct but also local proton sources to facilitate the C-O bond breaking.

7.
J Am Chem Soc ; 139(5): 1778-1781, 2017 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-28112923

RESUMO

The paddle-wheel type cluster Co2(RCOO)4(LT)2 (R = substituent group, LT = terminal ligand), possessing unusual metal coordination geometry compared with other cobalt compounds, may display high catalytic activity but is highly unstable especially in water. Here, we show that with judicious considerations of the host/guest geometries and modular synthetic strategies, the labile dicobalt clusters can be immobilized and stabilized in a metal-organic framework (MOF) as coordinative guests. The Fe(na)4(LT) fragment in the MOF [{Fe3(µ3-O)(bdc)3}4{Fe(na)4(LT)}3] (H2bdc = 1,4-benzenedicaboxylic acid, Hna = nicotinic acid) can be removed to give [{Fe3(µ3-O)(bdc)3}4] with a unique framework connectivity possessing suitable distribution of open metal sites for binding the dicobalt cluster in the form of Co2(na)4(LT)2. After two-step, single-crystal to single-crystal, postsynthetic modifications, a thermal-, water-, and alkaline-stable MOF [{Fe3(µ3-O)(bdc)3}4{Co2(na)4(LT)2}3] containing the desired dicobalt cluster was obtained, giving extraordinarily high electrocatalytic oxygen evolution activity in water at pH = 13 with overpotential as low as 225 mV at 10.0 mA cm-2.

8.
J BUON ; 22(1): 94-101, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28365941

RESUMO

PURPOSE: To explore the chemoprotective effect of umbelliferone (UF) on prostate cancer cell lines, i.e. primary stage (LnCap) and last stage (PC3) prostate cancer together with the effect on the induction of apoptosis and alteration on cell cycle arrest. METHODS: Various concentrations of UF were evaluated against the different prostate cancer cell lines. Lipopolysaccharide (LPS) induced cytokines related factor profiling, proinflammatory cytokines, and inflammatory mediators were studied using Western blot analysis. RESULTS: UF showed significant apoptotic effect. Moreover, treatment with UF did not show apoptosis or cell cycle arrest on the non-cancerous cells including BHP-1, suggesting a selective tumor cell specific effect. UF treatment also enhanced the expression of Bax in PC3 cells, but had no significant effect on the activation of nuclear factor κB (NF-κB). Thus, the apoptosis induction was independent of NF-κB activation. CONCLUSION: The results of the present investigation confirmed the chemoprotective effect of UF in early-stage (Ln- Cap) and late-stage (PC3) prostate cancer cells.


Assuntos
Anticarcinógenos/farmacologia , Umbeliferonas/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Masculino , NF-kappa B/fisiologia , Proteína X Associada a bcl-2/análise
9.
Chemistry ; 20(10): 2840-8, 2014 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-24590496

RESUMO

Reactions of hexaniobate with vanadate in the presence of Ni(2+) , Zn(2+) , or Cu(2+) have furnished three high-nuclear vanadium cluster-substituted heteropolyoxoniobates (HPNs): {Ni(en)3 }5 H{V(V) Nb8 V(IV) 8 O44 }⋅9 H2 O (1), (H2 en)Na2 [{Zn(en)2 (Hen)}{Zn(en)2 (H2 O)}2 {PNb8 V(IV) 8 O44 }]⋅11 H2 O (2), and Na{Cu(en)2 }3 {[Cu(en)2 ]2 [PNb8 V(IV) 8 O44 ]}⋅11 H2 O (3) (en=1,2-diaminoethane). Their structures have been determined and characterized by single-crystal X-ray diffraction analysis, thermogravimetric analysis (TGA), and elemental analysis. Structural analysis has revealed that compounds 1-3 contain similar {V8 }-substituted [X(V) Nb8 V(IV) 8 O44 ](11-) (X=P, V) clusters, obtained by inserting a {V8 } ring into tetravacant HPN [XNb8 O36 ](27-) . To the best of our knowledge, compounds 1-3 represent the first high-nuclear vanadium cluster-substituted HPNs, and compound 1 is the largest vanadoniobate cluster yet obtained in HPN chemistry. Nickel and zinc cations have been introduced into HPNs for the first time, which might promise a more diverse set of structures in this family. Antitumor studies have indicated that compounds 1 and 2 exhibit high activity against human gastric cancer SGC-7901 cells, SC-1680 cells, and MG-63 cells.


Assuntos
Antineoplásicos/síntese química , Neoplasias Gástricas/química , Neoplasias Gástricas/tratamento farmacológico , Elementos de Transição/química , Vanádio/química , Antineoplásicos/química , Linhagem Celular Tumoral , Cristalografia por Raios X , Humanos , Estrutura Molecular
10.
Chem Sci ; 10(42): 9859-9864, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-32015809

RESUMO

Extensive efforts have been devoted to developing efficient and durable catalysts for water oxidation. Herein, we report a highly stable metal-organic framework that shows high catalytic activity and durability for electrically driven (an overpotential of 430 mV at 10 mA cm-2 in neutral aqueous solution) and photodriven (a turnover frequency of 16 s-1 and 12 000 cycles) water oxidation, representing the best catalyst for water oxidation reported to date. Computational simulation and isotope tracing experiments showed that the µ4-OH group of the {Co8(µ4-OH)6} unit participates in the water oxidation reaction to offer an oxygen vacancy site with near-optimal OH- adsorption energy.

11.
Dalton Trans ; 45(10): 4269-73, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26575992

RESUMO

By using pyridyl derivatives 4-cyanopyridine (4-pyCN) or nicotinate (na(-)) as terminal ligands (L(T)) to decorate the flexible trigonal-prismatic trinuclear metal carboxylate M3(µ3-O/µ3-OH)(RCOO)6(L(T))3 clusters, a theoretically predicted uninodal 6-connected flu-e network for [M3(µ3-O/µ3-OH)(bdc)3(L(T))3] (H2bdc = 1,4-benzenedicarboxylic acid) has been realized in three new porous coordination frameworks. The flu-e topology is isomeric to the uninodal 6-connected acs (MIL-88) and tetranodal 6-connected mtn-e (MIL-101) ones observed in the classic metal carboxylate framework materials, but comprises of unique cubic cages which require exceptional conformation for the trinuclear clusters. The weak coordinating 4-pyCN terminal ligands tend to leave the clusters during thermal activation, leading to framework distortion and reduction of the long-range order of the flu-e network, which can only be restored by 4-pyCN instead of other guest molecules. On the other hand, the carboxylate ends of the adjacent na(-) ligands coordinate with additional metal ions to crosslink the coordination networks as new binodal 4,9-connected networks with remarkably enhanced thermal/chemical stability and porosity.

12.
Chem Commun (Camb) ; 50(45): 6017-9, 2014 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-24769641

RESUMO

Two phosphoniobate-based 3D frameworks were firstly constructed using the hexa-capped Keggin polyoxoniobates [PNb12O40(VO)6](3-) and copper cations. Photocatalytic studies indicated that the hybrid materials exhibit photocatalytic hydrogen evolution activity.


Assuntos
Hidrogênio/química , Nióbio/química , Vanadatos/química , Catálise
13.
Dalton Trans ; 42(16): 5812-7, 2013 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-23455352

RESUMO

An unprecedented organic-inorganic hybrid germanoniobate compound Na4[Cu(en)2(H2O)2]5[Na6Ge8Nb32O108H8(OH)4]·41H2O (1) was synthesized under the hydrothermal condition. In compound 1, the {Nb16} cage containing four {GeO4} tetrahedra in its internal cavity results in a heteropolyniobate anion [H4Ge4Nb16O54(OH)2](10-) ({Ge4Nb16}), which is connected by a {Na6} cluster into the first germanoniobate-based sandwich-type structure. Further, the sandwich germanoniobates are connected by [Na2Cu(en)2O6H8] groups into a porous network with one dimensional channels along the a-axis. Photocatalytic study reveals that compound 1 exhibits good photocatalytic activity for the degradation of methylene blue.


Assuntos
Complexos de Coordenação/química , Cobre/química , Germânio/química , Raios Ultravioleta , Catálise , Complexos de Coordenação/síntese química , Cristalografia por Raios X , Concentração de Íons de Hidrogênio , Azul de Metileno/química , Conformação Molecular
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