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BACKGROUND: Accumulating evidence has proved the significant influence of long non-coding RNAs (lncRNAs) in cancer formation and development, including PCa. METHODS: The role of LINC00689 in PCa was confirmed by RT-qPCR, MTT, colony formation, flow cytometry, western blot and transwell assays. Besides, the binding ability between LINC00689 and miR-496 was validated by using luciferase reporter assay. Then RT-qPCR, RIP and luciferase reporter and western blot assays were employed to verify the interactions among LINC00689, miR-496 and CTNNB1. Furthermore, the rescuing role of CTNNB1 in Wnt pathway was proved by RT-qPCR, TOP/FOP Flash and western blot assays. RESULTS: LINC00689 was upregulated in PCa tissues and cells as well as at the terminal stage. Further, knock down of LINC00689 repressed PCa cell proliferation, migration and invasion, and initiated PCa cell apoptosis. Additionally, miR-496 inhibitor and pcDNA3.1/CTNNB1 could neutralize the prohibitive effects of LINC00689 silencing on cell proliferation, migration and invasion, meanwhile, could offset the encouraging role of knocking down LINC00689 in cell apoptosis. Moreover, CTNNB1 upregulation exerted redemptive function in Wnt pathway inhibited by LINC00689 depletion. CONCLUSIONS: To sum up, LINC00689 promotes PCa progression via regulating miR-496/CTNNB1 to activate Wnt pathway, which may contribute to research about new targets for PCa treatment.
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Ozone-biological activated carbon (O3-BAC) process has been proved to be an efficient and cost-effective technology in advanced treatment of drinking water. However, O3-BAC raises strict requirements in adsorption, hydrodynamic and regeneration performances, which one single activated carbon could hardly all-sided meet. Blending activated carbons seems to be an appropriate and economically feasible method to deal with the issue. Thus, the uniformity and stability of activated carbon blends during water treatment, especially in backwashing process are of great importance. In this paper, cyclic experiments of downward adsorption and upward backwash on 11 typical commercial granular coal-based activated carbons and their blends were carried out in column test. Hydrodynamic performances such as bed expansion rate and bed pressure drop were measured. The uniformity and stability of activated carbon blends were investigated by determining iodine number of samples collected from different heights of activated carbon bed. Then, both traditional regression methods and back-propagation neural network model were utilized to predict superficial velocity at 30% bed expansion rate and maximum bed pressure drop of activated carbon blends. The results indicate that water backwashing process has no effect on the composition proportion of activated carbon blends, and slightly changes the particle distribution of activated carbon bed regarding pore structure and adsorption capacity. A three-layer back-propagation neural network model for superficial velocity at 30% bed expansion rate yields mean relative errors of 2.17%, which is much lower than that given by traditional regression methods such as 5.53% (weighted average), 4.08% (linear) and 4.06% (polynomial). Moreover, the back-propagation neural network model for maximum bed pressure drop yields mean relative errors of 1.37%, which is much lower than that given by traditional regression methods such as 4.31% (weighted average), 4.28% (linear) and 4.22% (polynomial). The non-linear relationships can be accurately identified by the back-propagation neural network model.
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Poluentes Químicos da Água , Purificação da Água , Adsorção , Carvão Vegetal , HidrodinâmicaRESUMO
BACKGROUND: MicroRNA (miRNA) pathway genes have been widely reported to participate in several physiological events in insect lifecycles. The cigarette beetle Lasioderma serricorne is an economically important storage pest worldwide. However, the functions of miRNA pathway genes in L. serricorne remain to be clarified. Herein, we investigated the function of molting and reproduction of the miRNA pathway in L. serricorne. RESULTS: LsDicer-1, LsArgonaute-1, LsLoquacious and LsExportin-5 were universally expressed in adults, whereas LsPasha and LsDrosha were mainly expressed in the pupae. The genes presented different patterns in various tissues. Silencing of LsDicer-1, LsArgonaute-1, LsDrosha and LsExportin-5 resulted in a high proportion of wing deformities and molting defects. Silencing of LsDicer-1, LsArgonaute-1, LsPasha and LsLoquacious affected the development of the ovary and the maturation of oocytes, resulting in a significant decrease in fecundity. Further investigation revealed that the decreases in LsDicer-1 and LsArgonaute-1 expression destroyed follicular epithelia and delayed vitellogenesis and oocyte development. In addition, the expression levels of several miRNAs (let-7, let-7-5p, miR-8-3p, miR-8-5p, miR-9c-5p, miR-71, miR-252-5p, miR-277-3p, miR-263b and Novel-miR-50) were decreased significantly after knockdown of these miRNA pathway core genes, indicating that they played important roles in regulating miRNA-mediated gene expression. CONCLUSION: The results indicate that miRNA pathway genes play important roles in the molting, ovarian development and female fecundity of L. serricorne, and thus are potentially suitable target genes for developing an RNAi strategy against a major pest of stored products. © 2024 Society of Chemical Industry.
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Besouros , MicroRNAs , Muda , Reprodução , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Muda/genética , Besouros/genética , Besouros/fisiologia , Besouros/crescimento & desenvolvimento , Reprodução/genética , Feminino , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Genes de Insetos , MasculinoRESUMO
Background: The predominant and most prevalent form of metastatic bladder cancer (BCa) is lymphatic metastasis, which is associated with a highly dismal prognosis for patients. Aging-related genes (ARGs) are believed to contribute significantly to tumor development. However, the effect of ARGs on lymphatic metastasis of BCa is unclear. This research sought to establish a prognosis model based on ARGs associated with lymphatic metastasis in BCa. Methods: We downloaded BCa data from the TCGA and GEO databases and ARGs from the Aging Atlas database. The least absolute shrinkage and selection operator (LASSO) approach was applied to obtain the characteristic ARGs of risk signature in the TCGA cohort. Verification was done using the GSE13507 dataset. The R package 'ConsensusClusterPlus' was employed to identify the molecular subtypes based on the characteristic ARGs. Protein-Protein interaction network, MCODE analysis, enrichment analysis (KEGG, GO, GSEA), and immune infiltration analysis were performed to investigate underlying mechanisms. EdU, migration and invasion assays, wound healing assays, immunofluorescence staining, and quantitative polymerase chain reaction were conducted to evaluate the impact of ELN on the proliferative, migratory, and invasive capacities of BCa cells. Results: We identified 20 differently expressed ARGs. A four ARGs risk signature (EFEMP1, UCHL1, TP63, ELN) was constructed in the TCGA cohort. The high-risk group (category) recorded a reduced overall survival (OS) rate relative to the low-risk category (hazard ratio, 2.15; P <0.001). The risk score could predict lymphatic metastasis in TCGA cohort (AUC=0.67). The GSE13507 dataset was employed to verify the validity of this risk score. Based on the four ARGs, two distinct aging profiles (Cluster 1 and Cluster 2) were discovered utilizing the ConsensusClusterPlus, and Cluster 2 possessed a favorable OS in contrast with Cluster 1 (hazard ratio, 0.69; P =0.02). Classical tumor signaling pathways, ECM-associated signaling pathways, and immune-related signaling pathways participate in BCa progression. ELN recombinant protein affected the expression of collagen and increased migration and invasiveness in BCa cells. Conclusion: We constructed a four-ARG risk signature and identified two aging molecular subtypes. This signature could serve as an effective survival predictor for patients with BCa.
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Low-rank coal, such as Shengli lignite (SL) and Datong bitumite (DT), has abundant reserves and is low in cost. Due to its high moisture content, abundant oxygen-containing groups, high ash content and low calorific value, low-rank coal is mainly used in a low-cost method of direct combustion. For better value-added utilization of SL and DT, a novel strategy has been developed for the preparation of oxygen-rich hierarchical porous carbons (HPCs) by hydrothermal carbonization (HTC), followed by steam activation. In this paper, firstly, the physical and chemical properties of SL and DT were improved by HTC pretreatment, bringing them closer to high rank coal. Then, the effects of HTC pretreatment and activation temperature on the properties of the HPCs were investigated in detail. The results show that the HPCs have mainly microporous structures (the microporosity of 200-SLHPC-900 is 79.58%) based on the N2 adsorption-desorption isotherm analysis and exhibit a higher specific surface area (SSA) and larger pore volume (25.02% and 2.69% improvement for 200-SLHPC-900; 4.93% and 14.25% increase for 200-DTHPC-900, respectively) after HTC pretreatment. The two types of HPCs also present good adsorption performance. The iodine adsorption value of lignite-based HPC presents an increase of 13.72% from 503 mg g-1 to 572 mg g-1, while the value of bitumite-based HPC increases up to 924 mg g-1. A preliminary additional HTC step is therefore an effective method by which to promote the performance of low-rank coal based porous carbon. The process of hydrothermal carbonization and steam activation is a cost-effective and environmentally-friendly preparation method, which omits the use of a chemical activator and reduces the step of alkaline waste liquid discharge compared with the route of carbonization and chemical activation.
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The preparation of activated carbon (AC) is a promising approach for the efficient utilization of Zhundong high-alkali coal. The volatilization and release of alkali and alkaline earth metal (AAEM) species can be effectively inhibited by using a lower operating temperature and a carbon matrix. However, the long time of the pyrolysis and activation process may promote the release of the AAEM from the coal during the process. Therefore, it is necessary to explore the transformation of AAEM during the preparation of AC from Zhundong high-alkali coal, and the cleanness of this process is evaluated accurately. In this study, the evolution of AAEM, distribution, and chemical speciation is characterized before and after the preparation of AC from the coal, and then thermodynamic calculations were performed using FactSage to simulate the transformation of AAEM in the coupled process of pyrolysis and activation. The results showed that in the process of AC preparation, the AAEM species inside the carbon matrix moved towards the surface of the AC with the aid of released volatiles and the activation reaction. Some Na and K species were released due to their weak binding with the carbon matrix and this resulted in the loss of Na and K content, whereas Mg and Ca were closely combined with the carbon matrix and were enriched in the AC. Furthermore, the defects and amorphous structure of the AC prepared with H2O activation were more than that of the AC prepared with CO2 activation, which meant that more of the AAEM species were exposed to the high temperature environment. As a result, the loss of AAEM content in the AC with H2O activation was higher than that in the AC with CO2 activation. In this process, a small amount of highly volatile and corrosive AAEM was produced, and the release of volatile matter and the consumption of the carbon matrix were the main factors for the AAEM loss. Therefore, the preparation of AC from Zhundong high-alkali coal is a viable method for its clean use.
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Zhundong coal can significantly reduce the preparation temperature of activated carbon (AC) due to the high contents of alkali and alkaline earth metals (AAEMs) present in it. Moreover, because of its lower operating temperature and the presence of carbon matrix, Zhundong coal can effectively inhibit the release of AAEM during the preparation of AC. For these reasons, the preparation of AC from Zhundong coal is a promising approach for the clean utilization of Zhundong coal. Accordingly, this study was aimed to investigate optimum conditions for the preparation of AC from Zhundong coal. For this purpose, at first, Raman spectroscopy was used to determine the conditions for an optimal carbonization process using a coal sample; then, the evolution of the pore structure of AC under different conditions was examined by small-angle X-ray scattering (SAXS) and the N2 adsorption analyser. Furthermore, environmental scanning electron microscopy (ESEM) was performed to analyze the surface morphology of AC. Finally, by dividing the activation process into gas-solid diffusion and activation reactions, a mechanism for the evolution of pore structure during the preparation of AC was proposed. The results showed that the char with an amorphous structure and less graphite-like carbon, which was obtained by heating Zhundong coal from room temperature to 600 °C at 5 °C min-1 under the protection of N2 and then maintaining it at this temperature for 60 min, is suitable for the subsequent activation process. At low temperatures, the diffusion of H2O was dominant in the activation process, and the weak gas-solid reaction resulted in poor development of the pore structure; on the other hand, the CO2 activation reaction mainly occurred on the surface of the char due to the poor diffusion of CO2, and then, the produced pores could improve the diffusion of CO2; this led to significant development of the pore structure. With an increase in temperature, the H2O diffusion reaction was enhanced, and the pore structure of AC was completely developed; however, the diffusion of CO2 reduced with an enhancement in the CO2 activation reaction, leading to the consumption of carbon matrix by CO2 gasification instead of pore formation by the CO2 activation reaction. Therefore, proper utilization of the unique characteristics of H2O and CO2 during pore formation is important to control the activation process.
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In this work, isotropic pitch precursors are synthesized by the bromination-debromination method with ethylene bottom oil (EO) as the raw material and bromine as the initiator for pitch formation and condensation reactions. The aggregation structure, molecular weight distribution, and molecular structure of isotropic pitch precursors are characterized by thermal mechanical analyzer (TMA), MALDI TOF-MS, and 13C NMR, respectively, for revealing the mechanism of synthesis of isotropic pitch precursors. The results show that at low bromine concentrations, polycyclic aromatic hydrocarbons (PAHs) were mainly ordered in cross-linked structures by bromination-debromination through substitution reactions of side chains. The condensed reactivity can be improved by the effect of bromine, meaning that condensation reaction was aggravated by the method of bromination-dehydrobromination. In the presence of excess bromine, the cross-linked stereo structure of PAHs changed to the planar structure of condensed PAHs, which was not conducive to the subsequent spinning and preparation of carbon fibers.
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OBJECTIVE: To assess the possibility of ureter tissue engineering using vessel extracellular matrix (VECM) and differentiated urine-derived stem cells (USCs) in a rabbit model. METHODS: VECM was prepared by a modified technique. USCs were isolated from human urine samples and cultured with an induction medium for the differentiation of the cells into urothelium and smooth muscle phenotypes. For contractile phenotype conversion, the induced smooth muscle cells were transfected with the miR-199a-5p plasmid. The differentiated cells were seeded onto VECM and cultured under dynamic conditions in vitro for 2â¯weeks. The graft was tubularized and wrapped by two layers of the omentum of a rabbit for vascularization. Then, the maturated graft was used for ureter reconstruction in vivo. RESULTS: VECM has microporous structures that allow cell infiltration and exhibit adequate biocompatibility with seeding cells. USCs were isolated and identified by flow cytometry. After induction, the urothelium phenotype gene was confirmed at mRNA and protein levels. With the combined induction by TGF-ß1 and miR-199a-5p, the differentiated cells can express the smooth muscle phenotype gene and convert to the contractile phenotype. After seeding cells onto VECM, the induced urothelium cells formed a single epithelial layer, and the induced smooth muscle cells formed a few cell layers during dynamic culture. After 3â¯weeks of omental maturation, tubular graft was vascularized. At 2â¯months post ureter reconstruction, histological evaluation showed a clearly layered structure of ureter with multilayered urothelium over the organized smooth muscle tissue. CONCLUSION: By seeding differentiated USCs onto VECM, a tissue-engineered graft could form multilayered urothelium and organized smooth muscle tissue after ureteral reconstruction in vivo. STATEMENT OF SIGNIFICANCE: Cell-based tissue engineering offers an alternative technique for urinary tract reconstruction. In this work, we describe a novel strategy for ureter tissue engineering. We modified the techniques of vessel extracellular matrix (VECM) preparation and used a dynamic culture system for seeding cells onto VECM. We found that VECM had the trait of containing VEGF and exhibited blood vessel formation potential. Urine-derived stem cells (USCs) could be differentiated into urothelial cells and functional contractile phenotype smooth muscle cells in vitro. By seeding differentiated USCs onto VECM, a tissue-engineered graft could form multilayered urothelium and organized smooth muscle tissue after ureteral reconstruction in vivo. This strategy might be applied in clinical research for the treatment of long-segment ureteral defect.
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Diferenciação Celular , Matriz Extracelular/metabolismo , Células-Tronco/citologia , Engenharia Tecidual/métodos , Ureter/fisiologia , Urina/citologia , Animais , Proliferação de Células , Forma Celular , Matriz Extracelular/ultraestrutura , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Masculino , Camundongos Nus , Contração Muscular , Miócitos de Músculo Liso/metabolismo , Omento/fisiologia , Fenótipo , Coelhos , Urotélio/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
A novel truncated form (residues 1-214, with a randomized C-terminal tail) of the ligand-binding extracellular domain (ECD) of the human alpha1 glycine receptor (GlyR), with amino acids from the corresponding sequence of an acetylcholine binding protein (AChBP) substituted for two relatively hydrophobic membrane-proximal loops, was overexpressed using a baculovirus expression system. The mutant GlyR ECD, named GlyBP, was present in both soluble and membrane-associated fractions after cell lysis, though only the latter appeared to be in a native-like conformation capable of binding strychnine, a GlyR specific antagonist. The membrane-associated GlyBP was solubilized, and detergent/lipid/protein micelles were affinity purified. After detergent removal, GlyBP may be isolated in either aqueous or vesicular form. Binding assays and spectroscopic studies using circular dichroism and FRET are consistent with both forms adopting equivalent native-like conformations. Thus, GlyBP may be isolated as a soluble or membrane-associated assembly that serves as a structural and functional homologue of the ECD of GlyR.
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Estrutura Terciária de Proteína , Receptores de Glicina/química , Receptores de Glicina/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Transferência Ressonante de Energia de Fluorescência , Humanos , Ligantes , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Receptores de Glicina/genéticaRESUMO
YciF is a protein that is up-regulated when bacteria experience stress conditions, and is highly conserved in a range of bacterial species. YciF has no known structure or biochemical function. To learn more about its potential molecular function and its role in the bacterial stress response, we solved the crystal structure of YciF at 2.0 Angstrom resolution by the multiple wavelength anomalous diffraction (MAD) technique. YciF is a dimer in solution, and forms a homodimer in the crystal asymmetric unit. The two monomers form a dimer with a molecular twofold axis, with a significant burial of solvent-accessible surface area. The protein is an all-alpha protein composed of five helices: a four-helix bundle, and a short additional helix at the dimer interface. The protein is structurally similar to portions of the diiron-containing proteins, rubrerythrin and the Bacillus anthracis Dlp-2.
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Cristalografia por Raios X/métodos , Proteínas de Escherichia coli/química , Escherichia coli/química , Proteínas de Choque Térmico/química , Sequência de Aminoácidos , Bacillus anthracis/química , Proteínas de Bactérias/química , Sítios de Ligação , Dimerização , Ferredoxinas/química , Hemeritrina , Ligantes , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Rubredoxinas , Homologia de Sequência de AminoácidosRESUMO
Ureter reconstruction is still a tough task for urologist. Cell-based tissue engineering serves a better technique for patients with long segments of ureter defect who need ureter reconstruction. In this study, we sought to evaluate the differentiation potential of adipose derived stem cells (ADSCs) into urothelial lineage and smooth muscle lineage and to assess the possibility of ureter reconstruction using differentiated cells seeded vessel extracellular matrix (VECM) in a rabbit model. ADSCs were isolated from adipose tissue and identified in vitro. Subsequently, they were cultured with induction medium for urothelium and smooth muscle phenotypes differentiation. After 14 days inducing, differentiation was evaluated by Quantitative PCR and western blot studies. After fluorescent protein labeling, the differentiated cells were seeded onto VECM and cultured under dynamic conditions in vitro. After 7 days culturing, the cell-seeded graft was tubularized and wrapped by two layers of the omentum in a rabbit. Three weeks later, the maturated graft was used for ureter reconstruction in vivo. The ADSCs were isolated and cultured in vitro. Flow cytometry demonstrated that the ADSCs expressed CD29 and CD90, but did not express CD34. After induction, urothelium phenotypes gene (cytokeratin 7) and smooth muscle expression gene (a-SMA and SM-MHC) was confirmed in mRNA and protein level. After cells seeding onto VECM, the induced urothelium cells formed a single epithelial layer, and the induced smooth muscle cells formed a few cell layers during dynamic culture. After 3 weeks of omental maturation, tubular graft was vascularized and comprised epithelial layer positively with cytokeratin 7, cytokeratin 20 on the luminal aspect. At 8 weeks post ureter reconstruction, histological evaluation showed a clearly layered structure of ureter with terminally differentiated multilayered urothelium positively with cytokeratin 20 and uroplakin III over connective smooth muscle tissue positively with a-SMA and SM-MHC. The labeled induced cells could be observed in the reconstructed ureter. We demonstrated that ADSCs could differentiate into urothelial and smooth muscle lineage. Tissue engineered graft by these differentiated cells seeded on VECM could be employed to long segments ureter reconstruction after omental maturation in vivo.
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The mRNA of Escherichia coli yedU gene is induced 31-fold upon heat shock. The 31-kD YedU protein, also calls Hsp31, is highly conserved in several human pathogens and has chaperone activity. We solved the crystal structure of YedU at 2.2 A resolution. YedU monomer has an alpha/beta/alpha sandwich domain and a small alpha/beta domain. YedU is a dimer in solution, and its crystal structure indicates that a significant amount of surface area is buried upon dimerization. There is an extended hydrophobic patch that crosses the dimer interface on the surface of the protein. This hydrophobic patch is likely the substrate-binding site responsible for the chaperone activity. The structure also reveals a potential protease-like catalytic triad composed of Cys184, His185, and Asp213, although no enzymatic activity could be identified. YedU coordinates a metal ion using His85, His122, and Glu90. This 2-His-1-carboxylate motif is present in carboxypeptidase A (a zinc enzyme), and a number of dioxygenases and hydroxylases that utilize iron as a cofactor, suggesting another potential function for YedU.
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Domínio Catalítico , Proteínas de Escherichia coli/química , Proteínas de Choque Térmico/química , Chaperonas Moleculares/química , Motivos de Aminoácidos/genética , Sequência de Aminoácidos , Ácido Aspártico/química , Ácido Aspártico/genética , Sítios de Ligação/genética , Domínio Catalítico/genética , Cristalografia por Raios X , Cisteína/química , Cisteína/genética , Dimerização , Processamento Eletrônico de Dados , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/fisiologia , Ácido Glutâmico/química , Ácido Glutâmico/genética , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/fisiologia , Histidina/química , Histidina/genética , Interações Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Chaperonas Moleculares/genética , Chaperonas Moleculares/fisiologia , Dados de Sequência Molecular , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Homologia de Sequência de Aminoácidos , Homologia Estrutural de Proteína , Zinco/químicaRESUMO
The stress protein Escherichia coli YciE was overexpressed and purified in three chromatographic steps. Crystals were obtained using PEG 4000 as a precipitant. The YciE protein crystals diffracted to 3.0 A resolution using a rotating-anode X-ray source. The lattice type is rhombohedral, with unit-cell parameters a = b = 64.2, c = 167.9 A, alpha = beta = 90, gamma = 120 degrees. The crystal belongs to space group R32.
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Cristalografia por Raios X/métodos , Proteínas de Escherichia coli/química , Escherichia coli/metabolismo , Proteínas de Choque Térmico/química , Cristalização , Proteínas de Choque Térmico/metabolismo , Proteínas Recombinantes/química , Raios XRESUMO
The Escherichia coli stress protein YciF was overexpressed and purified by three chromatographic steps. Crystals were obtained using ammonium sulfate as a precipitant. The YciF protein crystals diffracted beyond 2.25 A resolution using a rotating-anode X-ray source. The lattice type is rhombohedral, with unit-cell parameters a = b = 80.0, c = 131.03 A, alpha = beta = 90.0, gamma = 120.0 degrees. The crystal belongs to space group R32.
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Proteínas de Escherichia coli/química , Escherichia coli/metabolismo , Proteínas de Choque Térmico/química , Sequência de Aminoácidos , Cristalografia por Raios X , Dados de Sequência Molecular , Conformação Proteica , Proteínas Recombinantes/química , Homologia de Sequência de Aminoácidos , Difração de Raios XRESUMO
The putative receptor-binding domain (domain III) of the flavivirus Langat envelope glycoprotein has been crystallized using the hanging-drop vapor-diffusion method at 277 K. Two distinct crystal morphologies were observed to grow under the same conditions. The crystal forms both belong to a trigonal space group, P3(1)21 or P3(2)21, with unit-cell parameters a = 80.93, c = 132.1 A and a = 104.8, c = 219.5 A for forms I and II, respectively. Complete data sets to 2.9 and 3.35 A, respectively, have been collected at 100 K with Cu Kalpha X-rays from a rotating-anode generator.