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1.
Small ; 16(17): e1905853, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32249535

RESUMEN

The exploration of materials with reversible and stable electrochemical performance is crucial in energy storage, which can (de) intercalate all the alkali-metal ions (Li+ , Na+ , and K+ ). Although transition-metal chalcogenides are investigated continually, the design and controllable preparation of hierarchical nanostructure and subtle composite withstable properties are still great challenges. Herein, component-optimal Co0.85 Se1- x Sx nanoparticles are fabricated by in situ sulfidization of metal organic framework, which are wrapped by the S-doped graphene, constructing a hollow polyhedron framework with double carbon shells (CoSSe@C/G). Benefiting from the synergistic effect of composition regulation and architecture design by S-substitution, the electrochemical kinetic is enhanced by the boosted electrochemistry-active sites, and the volume variation is mitigated by the designed structure, resulting in the advanced alkali-ion storage performance. Thus, it delivers an outstanding reversible capacity of 636.2 mAh g-1 at 2 A g-1 after 1400 cycles for Li-ion batteries. Remarkably, satisfactory initial charge capacities of 548.1 and 532.9 mAh g-1 at 0.1 A g-1 can be obtained for Na-ion and K-ion batteries, respectively. The prominent performance combined with the theory calculation confirms that the synergistic strategy can improve the alkali-ion transportation and structure stability, providing an instructive guide for designing high-performance anode materials for universal alkali-ion storage.

2.
Bioprocess Biosyst Eng ; 43(11): 1931-1941, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32447513

RESUMEN

A purification system was constructed with the N-segment of the Npu DnaE split intein as an affinity ligand immobilized onto an epoxy-activated medium and the C-segment used as the cleavable tag fusing target protein. The affinity properties of C-tagged proteins adsorbed on IN affinity chromatography medium were studied with GFP as a model target protein. The saturated adsorption capacity and dynamic adsorption capacity reached 51.9-21.0 mg mL-1, respectively. With this system, two model proteins, GFP and alcohol dehydrogenase (ADH), has been successfully taglessly purified with regulation of Zn2+ and DTT. The yield, purification factor and purity of purified tagless GFP reached 39, 11.7 and 97%, respectively; while these values for purified tagless ADH were 38.2, 6.8 and 91%, respectively. These results showed that the system for Npu DnaE split intein-mediated affinity adsorption and in situ cleavage is a potential platform for recombinant protein production.


Asunto(s)
Biotecnología/métodos , Cromatografía de Afinidad/instrumentación , Cromatografía de Afinidad/métodos , Proteínas Recombinantes/aislamiento & purificación , Alcohol Deshidrogenasa/química , ADN Polimerasa III/genética , ADN Polimerasa III/metabolismo , Ditiotreitol/química , Escherichia coli/metabolismo , Proteínas Fluorescentes Verdes/química , Inteínas , Ligandos , Dominios Proteicos , Empalme de Proteína , Proteínas Recombinantes/química , Zinc/química
3.
Int J Syst Evol Microbiol ; 69(8): 2258-2262, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31125300

RESUMEN

Strain C4T, isolated from sea cucumber intestine in Weihai, Shandong, PR China, is a novel Gram-stain-negative, facultatively anaerobic, amphitrichously flagellated, short rod that grows as creamy white bacterial colonies on plates. Optimal growth of the strain was observed at 28-30 °C, pH 6.5-7.0 and at a concentration of 3 % NaCl. The G+C content of the genomic DNA was 49.0 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain C4T is a member of the genus Corallincola and was most similar to Corallincola platygyrae JLT2006T. The major cellular fatty acids of strain C4T were C16 : 1ω7c/iso-C15 : 0 2-OH, C16 : 0 and C18 : 1ω7c. The sole respiratory quinone was Q-8. The predominant polar lipids in strain C4T were phosphatidylethanolamine, phosphatidylglycerol and an unidentified phospholipid. Based on morphology and physiological characteristics, strain C4T should be classified as a novel species in the genus Corallincola, for which Corallincolaholothuriorum is proposed. The type strain is C4T (=ATCC BAA-2611T=CICC 10839T).


Asunto(s)
Gammaproteobacteria/clasificación , Filogenia , Pepinos de Mar/microbiología , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Gammaproteobacteria/aislamiento & purificación , Intestinos/microbiología , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/química
4.
Int J Syst Evol Microbiol ; 67(7): 2263-2267, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28691658

RESUMEN

A Gram-stain-negative, aerobic, non-gliding, rod-shaped and orange-coloured bacterium, designated strain P131T, was isolated from marine sediment of the coast of Weihai, China, and subjected to a polyphasic study. Strain P131T was found to grow optimally at 28-30 °C, at pH 7.0-7.5 and in the presence of 2-3 % (w/v) NaCl. In a phylogenetic analysis based on 16S rRNA gene sequences, strain P131T was found to belong to the genus Bizionia and exhibited 94.6-97.0 % 16S rRNA gene sequence similarity with recognized Bizionia species. The dominant cellular fatty acids of strain P131T were identified as iso-C15 : 0, iso-C15 : 0 G, iso-C17 : 0 3-OH and iso-C17 : 1ω9c. The predominant polar lipids were phosphatidylethanolamine, phospholipid, two aminolipids and two unidentified lipids. The predominant respiratory quinone was menaquinone MK-6 and the DNA G+C content was 36.7 mol%. On the basis of the phylogenetic and phenotypic evidence presented, strain P131T represents a novel species of the genus Bizionia, for which the name Bizionia sediminis sp. nov. is proposed. The type strain is P131T (=KCTC 42587T=MCCC 1H00124T).


Asunto(s)
Flavobacteriaceae/clasificación , Sedimentos Geológicos/microbiología , Filogenia , Agua de Mar/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Flavobacteriaceae/genética , Flavobacteriaceae/aislamiento & purificación , Fosfolípidos/química , Pigmentación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
5.
Int J Syst Evol Microbiol ; 67(6): 1932-1936, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28598301

RESUMEN

A Gram-stain-negative, non-motile, rod-shaped, red-pigmented, facultatively anaerobic bacterium, designated SS2-9T, was isolated from sediment collected from a sea cucumber culture pond located in Rongcheng, Shandong province, China. Cells of strain SS2-9T were approximately 0.3-0.5 µm in width and 1.5-6.0 µm in length. The strain was able to grow at 10-37 °C, at pH 6.5-8.5 and in the presence of 0.5-6.0 % (w/v) NaCl. It grew optimally at 28 °C and in the presence of 2.0 % (w/v) NaCl. The DNA G+C content was 34.5 mol% and the sole respiratory quinone was menaquinone 6 (MK-6). The predominant cellular fatty acids were C15 : 0, iso-C15 : 1 G, iso-C15 : 0 and iso-C17 : 0 3-OH. The major polar lipids were phosphatidylethanolamine, an unidentified phospholipid, two unidentified aminolipids and four unidentified lipids. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain SS2-9T was phylogenetically related to members of the genus Aquimarina and was closely related to Aquimarina amphilecti 92VT (97.29 % similarity). On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain SS2-9T was considered to represent a novel species of the genus Aquimarina, for which the name Aquimarina rubra sp. nov. is proposed. The type strain is SS2-9T (=KCTC 52274T=MCCC 1H00142T).


Asunto(s)
Flavobacteriaceae/clasificación , Sedimentos Geológicos/microbiología , Filogenia , Pepinos de Mar/microbiología , Agua de Mar/microbiología , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Flavobacteriaceae/genética , Flavobacteriaceae/aislamiento & purificación , Fosfolípidos/química , Estanques/microbiología , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
6.
J Sep Sci ; 39(10): 1900-7, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27027849

RESUMEN

A type of mixed-mode chromatography was integrated with high-performance liquid chromatography for protein analysis and separation. The chromatographic behavior was tested using bovine serum albumin and lysozyme as model proteins. For the mixed-mode column, the silica beads were activated with γ-(2,3-epoxypropoxy)-propytrimethoxysilane and coupled with 4-mercaptopyridine as the functional ligand. The effects of pH, salt, and the organic solvent conditions of the mobile phase on the retention behavior were studied, which provided valuable clues for separation strategy. When eluted with a suitable pH gradient, salt concentration gradient, and acetonitrile content gradient, the separation behavior of bovine serum albumin and lysozyme could be controlled by altering the conditions of the mobile phase. The results indicated this type of chromatography might be a useful method for protein analysis and separation.


Asunto(s)
Muramidasa/análisis , Albúmina Sérica Bovina/análisis , Acetonitrilos/química , Animales , Bovinos , Cromatografía Líquida de Alta Presión , Concentración de Iones de Hidrógeno , Modelos Moleculares , Muramidasa/metabolismo , Dióxido de Silicio/química , Cloruro de Sodio/química
7.
Yi Chuan ; 36(7): 707-12, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25076036

RESUMEN

To verify the function of chalcone reductase gene (CHR1) in soybean Daidzein synthesis, CHR1 gene in soybean was cloned, and an RNAi expression vector pCPB-CHR1-RNAi was constructed. Four transformed plants in T0 generation and thirteen transformed plants in T1 generation of soybean "Jinong28" were obtained by agrobacterium-mediated genetic transformation, in which transcriptions of CHR1 gene were depressed. Southern blotting showed the functional fragment of pCPB-CHR1-RNAi was integrated into the genome of recipient soybean in the form of a single copy. Detection of the transcription of CHR1 gene using quantitative real-time PCR (qRT-PCR) showed that the expression of CHR1 gene in transformed plants decreased 60%-99% compared to the recipient soybean, while the content of isoliquiritigenin, the precursors of daidzein, decreased 38.7%. These results indicate that RNA interference can suppress the transcription of CHR1 gene expression successfully.


Asunto(s)
Oxidorreductasas de Alcohol/metabolismo , Glycine max/enzimología , Proteínas de Plantas/metabolismo , Oxidorreductasas de Alcohol/genética , Clonación Molecular , Regulación de la Expresión Génica de las Plantas , Isoflavonas/biosíntesis , Proteínas de Plantas/genética , Interferencia de ARN , Glycine max/genética , Transformación Genética
8.
Antonie Van Leeuwenhoek ; 104(3): 315-20, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23754662

RESUMEN

A novel Gram-negative, strictly aerobic, heterotrophic, non-motile and yellow-pigmented bacterial strain, designated HD4(T), was isolated from the sea urchin Hemicentrotus pulcherrimus collected from the Yellow Sea in China. Optimal growth of the strain was observed at 28-30 °C, pH 6.8-7.3, and in the presence of 3-5 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strain HD4(T) exhibited high similarity with the members of Salegentibacter (92.3-95.4 %). The DNA G+C content was 37.0 mol%, MK-6 was the main respiratory quinone and summed feature 3 (comprising iso-C15:0 2-OH/C16:1ω7c), iso-C15:0, iso-C17:0 3-OH and anteiso-C15:0 were the major cellular fatty acids. The predominant polar lipids in strain HD4(T) were phosphatidylethanolamine and two unknown lipids (L2, L4). Based on the phylogenetic, physiological and biochemical characteristics, strain HD4(T) should be classified as a novel species within the genus Salegentibacter, for which the name Salegentibacter echinorum sp. nov. is proposed. The type strain is HD4(T) (=CICC 10466(T) = NRRL B-59666(T)).


Asunto(s)
Bacterias Aerobias/clasificación , Bacterias Aerobias/aislamiento & purificación , Flavobacteriaceae/clasificación , Flavobacteriaceae/aislamiento & purificación , Hemicentrotus/microbiología , Animales , Bacterias Aerobias/genética , Técnicas de Tipificación Bacteriana , Composición de Base , China , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Ácidos Grasos/análisis , Flavobacteriaceae/genética , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Fosfolípidos/análisis , Filogenia , Pigmentos Biológicos/metabolismo , Quinonas/análisis , ARN Ribosómico 16S/genética , Agua de Mar , Análisis de Secuencia de ADN , Cloruro de Sodio/metabolismo , Temperatura
9.
IEEE Trans Pattern Anal Mach Intell ; 45(3): 3434-3445, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35544511

RESUMEN

Unsupervised domain adaptation (UDA) has recently become an appealing research topic in visual recognition, since it exploits all accessible well-labeled source data to train a model with high generalization on target domain without any annotations. However, due to the significant domain discrepancy, the bottleneck for UDA is to learn effective domain-invariant feature representations. To fight off such an obstacle, we propose a novel cross-domain learning framework named Maximum Structural Generation Discrepancy (MSGD) to accurately estimate and mitigate domain shift via introducing an intermediate domain. First, the cross-domain topological structure is explored to propagate target samples to generate a novel intermediate domain paired with the specific source instances. The intermediate domain plays as the bridge to gradually reduce distribution divergence across source and target domains. Concretely, the similar category semantic across source and intermediate features tends to naturally conduct the class-level alignment on eliminating their domain shift. In terms of no target annotation, the domain-level alignment manner is suitable to narrow down the distance between intermediate and target domains. Moreover, to produce high-quality generative instances, we develop the class-driven collaborative translation (CDCT) module to generate class-consistent cross-domain samples in each mini-batch with the assistance of pseudo-labels. Extensive experimental analyses on five domain adaptation benchmarks demonstrate the effectiveness of our MSGD on solving UDA problem.

10.
Artículo en Inglés | MEDLINE | ID: mdl-37028055

RESUMEN

Domain generalization (DG) aims to learn transferable knowledge from multiple source domains and generalize it to the unseen target domain. To achieve such expectation, the intuitive solution is to seek domain-invariant representations via generative adversarial mechanism or minimization of cross-domain discrepancy. However, the widespread imbalanced data scale problem across source domains and category in real-world applications becomes the key bottleneck of improving generalization ability of model due to its negative effect on learning the robust classification model. Motivated by this observation, we first formulate a practical and challenging imbalance domain generalization (IDG) scenario, and then propose a straightforward but effective novel method generative inference network (GINet), which augments reliable samples for minority domain/category to promote discriminative ability of the learned model. Concretely, GINet utilizes the available cross-domain images from the identical category and estimates their common latent variable, which derives to discover domain-invariant knowledge for unseen target domain. According to these latent variables, our GINet further generates more novel samples with optimal transport constraint and deploys them to enhance the desired model with more robustness and generalization ability. Considerable empirical analysis and ablation studies on three popular benchmarks under normal DG and IDG setups suggests the advantage of our method over other DG methods on elevating model generalization. The source code is available in GitHub https://github.com/HaifengXia/IDG.

11.
Artículo en Inglés | MEDLINE | ID: mdl-37037243

RESUMEN

Domain adaptation (DA) has recently drawn a lot of attention, as it facilitates unlabeled target learning by borrowing knowledge from an external source domain. Most existing DA solutions seek to align feature representations between the labeled source and unlabeled target data. However, the scarcity of target data easily results in negative transfer, as it misleads the cross DA to the dominance of the source. To address the challenging few-shot domain adaptation (FSDA) problem, in this article, we propose a novel marginalized augmented FSDA (MAF) approach to address the cross-domain distribution disparity and insufficiency of target data simultaneously. On the one hand, cross-domain continuity augmentation (CCA) synthesizes abundant intermediate patterns across domains leading to a continuous domain-invariant latent space. On the other hand, sufficient source-supervised semantic augmentation (SSA) is explored to progressively diversify the conditional distribution within and across domains. Moreover, the proposed augmentation strategies are implemented efficiently via an expected transferable cross-entropy (CE) loss over the augmented distribution instead of explicit data synthesis, and minimizing the upper bound of the expected loss introduces negligible extra computing cost. Experimentally, our method outperforms the state of the art in various FSDA benchmarks, which demonstrates the effectiveness and contribution of our work. Our source code is provided at https://github.com/scottjingtt/MAF.git.

12.
J Ind Microbiol Biotechnol ; 39(3): 495-502, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22009057

RESUMEN

The genes involved in L: -arginine biosynthesis in Corynebacterium crenatum are organized as the argCJBDFRGH cluster like in Corynebacterium glutamicum. However, the argC~H cluster of the C. crenatum SYPA 5-5, which is an industrialized L: -arginine producer, had a lethal mutation occurring in the ArgR repressor encoding gene. The argC~H cluster with an inactive argR was overexpressed in E. coli and C. crenatum. In the recombinant E. coli JM109 enzyme activities were increased, and more L: -arginine was found in the supernatants from L: -glutamine. When the argC~H cluster was overexpressed in C. crenatum under its native promoter Parg, L: -arginine production was increased by 24.9%, but the presence of the recombinant plasmid pJC-9039 had a negative effect on cell growth. Surprisingly, the DO value of the recombinant strain dropped gently and stayed at a lower level from 24 h to the end of fermentation. The results demonstrated an increasing utilization of oxygen and the distinct enhancement of unit cell L: -arginine yields with the cluster argC~H-bearing in C. crenatum SYPA-9039. This study provides a kind of Corynebacteria with improved L: -arginine-producing ability and an efficient elevation for producing amino acid. Moreover, the promoter Parg would be used as a valid promoter to express objective genes for metabolic engineering in Corynebacteria.


Asunto(s)
Arginina/metabolismo , Corynebacterium/metabolismo , Ingeniería Metabólica , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Corynebacterium/genética , Corynebacterium/crecimiento & desarrollo , Fermentación , Expresión Génica , Regulación Bacteriana de la Expresión Génica , Plásmidos
13.
World J Microbiol Biotechnol ; 28(4): 1563-74, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22805938

RESUMEN

The effects of culture conditions on 2,3-butanediol (2,3-BD) production and its possible scale-up have been studied. A newly isolated Bacillus amyloliquefaciens B10-127, belonged to GRAS microorganisms and showed a remarkable 2,3-BD producing potency, was used for this experiment. Corn steep liquor, soybean meal and ammonium citrate were found to be the key factors in the fermentation according to the results obtained from the Plackett-Burman experimental design. The optimal concentration range of the three factors was examined by the steepest ascent path, and their optimal concentration were further optimized via response surface methodological approach and determined to be 31.9, 22.0 and 5.58 g/l, respectively. The concentration of the obtained 2,3-BD increased significantly with optimized medium (62.7 g/l) when compared with unoptimized medium (45.7 g/l) and the 2,3-BD productivity was about 2.4-fold (The fermentation time was shorten from 72 to 42 h). To observe scale-up effects, batch fermentation was carried out at various working volumes. At a working volume of 20.0 l, the final 2,3-BD concentration and yield were 61.4 and 0.38 g/g at 36 h with a 2,3-BD productivity of 1.71 g/l h. This result shows similar amount of 2,3-BD obtained in lab-scale fermentation, and it is possible to scale up to larger fermentors without major problems.


Asunto(s)
Bacillus/metabolismo , Butileno Glicoles/metabolismo , Medios de Cultivo/química , Bacillus/clasificación , Bacillus/crecimiento & desarrollo , Bacillus/aislamiento & purificación , Biotecnología/métodos , ADN Bacteriano/química , ADN Bacteriano/genética , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Glycine max/metabolismo , Zea mays/metabolismo
14.
Yi Chuan ; 34(6): 749-56, 2012 Jun.
Artículo en Zh | MEDLINE | ID: mdl-22698747

RESUMEN

The zinc finger protein is one of the proteins with finger-like domain. Some of them are transcription factors which play important role in plant growth and plant resistance to abiotic stresses. In this paper, a novel C2H2-type zinc finger protein gene SCTF-1 (GenBank accession number JQ692081) was isolated from soybean (Glycine max (L.) Merr.) This gene has a 699 bp ORF (open reading frame) with no intron and encodes a 24.9 kDa protein with 233 amino acids. Its isoelectric point (pI) is 8.33. The SCTF-1 protein contains two typical C2H2-type zinc finger domains. Both of them have highly conserved amino acid sequence-QALGGH which is a particular characteristic of plant. Transient expression of the GFP-SCTF-1 protein in onion epidermal cell showed that SCTF-1 was localized in cell nuclei. RT-PCR results showed that SCTF-1 gene was expressed with high levels in flowers and leaves in soybean, but low in roots and stems. The expression of SCTF-1 gene was strongly induced by low temperature in the soybean seedlings. Overexpression of SCTF-1 enhanced cold tolerance of transgenic tobacco (Nicotiana tabacum L.) compared to the control.


Asunto(s)
Genes de Plantas , Glycine max/genética , Glycine max/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Dedos de Zinc/genética , Secuencia de Aminoácidos , Núcleo Celular/genética , Núcleo Celular/metabolismo , Clonación Molecular/métodos , Regulación de la Expresión Génica de las Plantas , Datos de Secuencia Molecular
15.
IEEE Trans Image Process ; 31: 3657-3668, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35576409

RESUMEN

Zero-shot sketch-based image retrieval (ZS-SBIR) has attracted great attention recently, due to the potential application of sketch-based retrieval under zero-shot scenarios, where the categories of query sketches and gallery photos are not observed in the training stage. However, it is still under insufficient exploration for the general and practical scenario when the query sketches and gallery photos contain both seen and unseen categories. Such a problem is defined as generalized zero-shot sketch-based image retrieval (GZS-SBIR), which is the focus of this work. To this end, we propose a novel Augmented Multi-modality Fusion (AMF) framework to generalize seen concepts to unobserved ones efficiently. Specifically, a novel knowledge discovery module named cross-domain augmentation is designed in both visual and semantic space to mimic novel knowledge unseen from the training stage, which is the key to handling the GZS-SBIR challenge. Moreover, a triplet domain alignment module is proposed to couple the cross-domain distribution between photo and sketch in visual space. To enhance the robustness of our model, we explore embedding propagation to refine both visual and semantic features by removing undesired noise. Eventually, visual-semantic fusion representations are concatenated for further domain discrimination and task-specific recognition, which tend to trigger the cross-domain alignment in both visual and semantic feature space. Experimental evaluations are conducted on popular ZS-SBIR benchmarks as well as a new evaluation protocol designed for GZS-SBIR from DomainNet dataset with more diverse sub-domains, and the promising results demonstrate the superiority of the proposed solution over other baselines. The source code is available at https://github.com/scottjingtt/AMF_GZS_SBIR.git.

16.
Biotechnol Prog ; 38(5): e3266, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35488391

RESUMEN

This research focuses on the construction of an affinity purification system based on Cfa DnaE split intein. Cfa DnaE intein is an artificially constructed intein with the advantages of a fast cleavage reaction and good stability. In a previous study, a purification system that uses Cfa intein as a tag was constructed, the separation of the target protein and the tag during the purification process was completed, and the purity of the purified target protein reached 98.21%. Guided by molecular docking results, we identified flexible regions in the split intein and inserted several glycines into the protein to decrease the stability of the Cfa IC , thereby improving the regenerability of the IN media. Inserting 6 glycines between amino acids 14 and 15 of IC improved the regeneration rate of IC -GFP on the column to approximately 96%.


Asunto(s)
ADN Polimerasa III , Inteínas , Cromatografía de Afinidad/métodos , ADN Polimerasa III/metabolismo , Glicina , Inteínas/genética , Simulación del Acoplamiento Molecular
17.
Chem Commun (Camb) ; 58(22): 3625-3628, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35201248

RESUMEN

We report the FeVOx porous nanorods on carbon cloth as a novel cathode material for flexible aqueous energy storage. It exhibits excellent electrochemical properties and cycling stability in supercapacitors and zinc-ion batteries. Moreover, this work makes significant progress for developing high-performance electrodes and provides a foundation for future research.

18.
J Basic Microbiol ; 51(6): 650-8, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21780143

RESUMEN

In the current study, a GRAS (Generally Recognized As Safe) strain of Bacillus amyloliquefaciens producing 2,3-butanediol (2,3-BD) designated as B10-127 was isolated in our lab. The strain B10-127 produced 2,3-BD effectively under the condition of 20% glucose (quality concentration), showed a high-glucose tolerance. The effects of initial glucose concentration, temperature, pH and agitation on 2,3-BD production were investigated in this work and the proper parameters were identified. Accordingly, the fed-batch culture of B10-127 in larger scales (5 l) showed a remarkable 2,3-BD producing potency. The maximum 2,3-BD concentration reached 92.3 g/l at 96 h with a 2,3-BD productivity of 0.96 g/l h. To our knowledge, the results were new records on 2,3-BD fermentation by Bacillus, which shown an excellent candidate for the microbial fermentation of 2,3-BD on an industrial scale.


Asunto(s)
Bacillus/metabolismo , Butileno Glicoles/metabolismo , Glucosa/metabolismo , Reactores Biológicos/microbiología , Fermentación , Concentración de Iones de Hidrógeno , Temperatura
19.
Se Pu ; 39(7): 764-770, 2021 Jul 08.
Artículo en Zh | MEDLINE | ID: mdl-34227375

RESUMEN

An analytical method based on headspace gas chromatography was developed for the determination of eight organic residues in ion exchange resins, methyl isopropyl ketone, methyl butyrate, 3-pentanone, 1,3-diethyl benzene, 1,4-diethyl benzene, dichloroethane, 1,3-dichlorobenzene, and methyl methacrylate. The organic residues in different types of resins were studied to provide a basis for the safe use of ion-exchange resins in food and medicine. The main factors (chromatographic column, equilibrium temperature, equilibrium time, flow rate, etc.) that affect the accuracy and sensitivity of the eight organic residues were investigated during instrument analysis. The extraction solvent and chromatographic conditions for the samples were optimized. According to the extraction efficiencies of methyl benzene, methyl alcohol and dimethyl sulfoxide, 2.0 g of the sample was extracted with dimethyl sulfoxide under ultrasonic conditions at 20 ℃. A DB-23 chromatographic column (60 m×0.32 mm×0.25 µm) and hydrogen flame ionization detector (FID) were selected for the GC method, and good separation and quantitative results were obtained for the eight organic residues. The process and conditions are summarized as follows. The equilibration time of the headspace sampler was 30 min, and the equilibrium temperature was 80 ℃. The temperature of the sampler was 240 ℃, while that of the FID detector was 300 ℃, with nitrogen being used as the carrier gas. The programmed temperature of the column was maintained at 60 ℃ for 16 min, then increased to 200 ℃ at a heating rate of 20 ℃/min, and maintained at this level for 2 min. The flow rate was 1.2 mL/min for detection. The external standard method was utilized for quantitative analysis. Good linear relationships were observed for the eight organic residues, and the correlation coefficients (R2) were all above 0.999 in the mass concentration range of 0.02-200 mg/L. The limits of detection (LODs) were 0.0050-0.0375 ng/g. The average recoveries for the eight organic residues were in the range of 82.3% to 109.2% at three spiked levels, and the relative standard deviation (RSD, n=6) was 1.06% to 4.16%. Eleven types of resin samples were detected by this method, and a certain amount of organic compounds were observed in the resin samples. The methyl methacrylate content in the methacrylate resin XAD761 was 414.4 µg/g, while that in the styrene resin LX-69B was as high as 470.8 µg/g. As opposed to traditional analytical methods, the present method has high sensitivity, good accuracy, and precision, with simple operation without derivatization or the need for acid-base treatment of the sample to reduce contamination. This method can be used to simultaneously detect a variety of organic residues in ion-exchange resins, so that the detection efficiency is significantly improved.

20.
Cancer Biomark ; 31(1): 39-46, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33749638

RESUMEN

BACKGROUND: EC (esophageal cancer) is a common cancer among people in the world. The molecular mechanism of FAM196B (family with sequence similarity 196 member B) in EC is still unclear. This article aimed to clarify the role of FAM196B in EC. METHODS: The expression of FAM196B in EC tissues was detected using qRT-PCR. The prognosis of FAM196B in EC patients was determined by log-rank kaplan-Meier survival analysis and Cox regression analysis. Furthermore, shRNA was used to knockdown the expression of FAM196B in EC cell lines. MTT, wound healing assays and western blot were used to determine the role of FAM196B in EC cells. RESULTS: In our research, we found that the expression of FAM196B was up-regulated in EC tissues. The increased expression of FAM196B was significantly correlated with differentiation, lymph node metastasis, stage, and poor survival. The proliferation and migration of EC cells were inhibited after FAM196B-shRNA transfection in vitro and vivo. The western blot result showed that FAM196B could regulate EMT. CONCLUSION: These results suggested that FAM196B severs as an oncogene and promotes cell proliferation and migration in EC. In addition, FAM196B may be a potential therapeutic target for EC patients.


Asunto(s)
Neoplasias Esofágicas/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Animales , Movimiento Celular , Proliferación Celular , Transición Epitelial-Mesenquimal , Humanos , Ratones , Ratones Desnudos , Persona de Mediana Edad
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