Pasteurella multocida major outer membrane protein (OmpH) has been previously characterized as a porin. The native OmpH from strain X-73 (serotype 1) but not recombinant protein from
Escherichia coli ...induced homologous protection in chickens. In this study OmpH sequences from 15
P. multocida serotypes as well as the CU vaccine strain were compared by sequence alignment and revealed high homology, with major variations confined to two discrete regions which were correspondingly predicted as two largest external loops. Secondary structures of OmpHs were predicted by sequence alignment of OmpHs with well defined porins and analyses of amphiphilicity, hydrophobic moment and antigenic index plots. Several synthetic peptides derived from predicted loop 2 and loop 5 of X-73 OmpH were synthesized as vaccine candidates. Vaccination studies in chickens showed that the cyclic synthetic peptide (Cyclic-L2) mimicking the predicted loop 2 induced 70% protection in chickens against strain X-73 challenge. This is the first report that a synthetic peptide mimicking the conformational epitopes of a native protein provide practical protection in target animal against bacterial infection.
Bovine viral diarrhea virus (BVDV) infections are enzootic in the cattle population and continue to cause significant economic losses to the beef and dairy industries worldwide. Extent of the damages ...has stimulated increasing interest in control programs directed at eradicating BVDV infections. Use of a BVDV marker vaccine would facilitate eradication efforts as a negatively marked vaccine would enable differentiation of infected from vaccinated animals (DIVA). We describe here the construction of three chimeric BVDVs containing glycoprotein E(rns) of heterologous pestiviruses and the evaluation of the chimera viruses as potential marker vaccines against BVDV infections. Chimeric NADL/G-E(rns), NADL/R-E(rns), and NADL/P-E(rns) were constructed by replacing the E(rns) gene of the full-length BVDV (NADL strain) genome with the E(rns) genes of giraffe (G-E(rns)), reindeer (R-E(rns)), or pronghorn antelope (P-E(rns)) pestiviruses, respectively. Each chimeric NADL virus was viable and infectious in RD 420 (bovine testicular) and BK-6 (bovine kidney) cells. By immunohistochemistry assays, NADL/G-E(rns) and NADL/R-E(rns) chimeric viruses reacted to BVDV E(rns) specific monoclonal antibody (mAb) 15C5, whereas the NADL/P-E(rns) chimeric virus did not. In an animal vaccination study, inactivated vaccines made from two chimeric viruses and the wild type NADL BVDV induced similar neutralizing antibody responses. NADL/P-E(rns)-vaccinated animals were distinguished from animals vaccinated with the wild type virus by means of a companion serological DIVA assay. These results show that chimeric NADL/P-E(rns) virus containing the E(rns) gene of pronghorn antelope pestivirus could be a potential marker vaccine candidate for use in a BVDV control and eradication program.
Highlights * Three chimeric bovine viral diarrhea viruses were constructed using overlapping PCR methods.*Chimeras contained glycoprotein Ernsof heterologous pestiviruses.*Each BVDV chimera was ...infectious in bovine cells and induced neutralizing antibody responses.*BVDV/P-Erns(pronghorn antelope)-vaccinated cattle were uniquely detectable serologically. * BVDV/P-Ernscould be a potential BVDV marker vaccine candidate for BVDV eradication programs.
Highlights ► Three chimeric bovine viral diarrhea viruses were constructed using overlapping PCR methods. ► Chimeras contained glycoprotein Erns of heterologous pestiviruses. ► Each BVDV chimera was ...infectious in bovine cells and induced neutralizing antibody responses. ► BVDV/P-Erns (pronghorn antelope)-vaccinated cattle were uniquely detectable serologically. ► BVDV/P-Erns could be a potential BVDV marker vaccine candidate for BVDV eradication programs.
The major outer membrane protein (OmpH) of Pasteurella multocida X-73 was purified by selective extraction with detergents, followed by size exclusion chromatography. The planar lipid bilayer assay ...showed that OmpH has pore-forming function. The average single channel conductance in 1.0 M KCl was 0.62 nS. The gene (ompH) encoding OmpH has been isolated and sequenced by construction of a genomic library and PCR techniques. The coding region of this gene is 1,059 bp long. The predicted primary protein is composed of 353 amino acids, with a 20-amino-acid signal peptide. The mature protein is composed of 333 amino acids with a molecular mass of 36,665 kDa. The ompH gene encoding mature protein has been expressed in Escherichia coli by using a regulatable expression system. The ompH gene was distributed among 15 P. multocida serotypes and strain CU. Protection studies showed that OmpH was able to induce homologous protection in chickens. These findings demonstrate that OmpH is a protective outer membrane porin of strain X-73 and is conserved among P. multocida somatic serotypes
The major outer membrane proteins (OmpH) of P. multocida strains X-73 and P-1059 were purified by selective extraction with detergents and size exclusion chromatography. The planar lipid bilayer ...assay showed that OmpH had pore-forming activity. The genes (ompH) encoding OmpHs of all P. multocida serotypes were cloned and sequenced. The coding regions for mature protein are composed of 954-999 base pairs, and the deduced mature proteins are composed of 318-333 amino acids. The amino acid compositions, sequences and hydropathy profiles of the deduced proteins (OmpHs) are similar to the superfamily of porins of Gram-negative bacteria. The OmpHs from different serotypes showed high homology in amino acid sequence (72.3% overall identity). Computer-aided secondary structure predictions revealed 16 anti-parallel beta-strands connected by 8 external loops and 8 short periplasmic turns. The genes encoding mature proteins of X-73 and P-1059 major outer membrane protein (OmpH) were expressed in E. coli. Protection studies showed that purified X-73 major outer membrane protein (OmpH) and a synthetic cyclic peptide derived from the predicted largest loop (loop 5) of X-73 OmpH induced homologous protection in chickens. The recombinant protein and synthetic linear peptides did not provide protection in chickens against homologous challenge.
The purpose of this study is to investigate the current status of heavy metal soil pollution in one of the cradles of industry in China, the Tiexi Industrial District in the city of Shenyang, ...Ninety-three soil samples were collected from the top 15cm of the soil layer and were analyzed for heavy metal concentrations of Pb, Cu, Cr, Zn, Mn, Cd, As and Hg. The data reveal a remarkable variation in heavy metal concentration among the sampled soils; the mean values of all the heavy metal concentrations were higher than the background values, and the mean concentrations of Pb, Cu, Cd and As were as high as 5.75, 5.08, 12.12 and 13.02 times their background values, respectively. The results of principal component analysis (PCA) indicate that Pb, Cu, Zn, Cd, As and Hg are closely associated with the first principal component (PC1), which explained 46.7% of the total variance, while Cr and Mn are mainly distributed with the second component (PC2), which explained 22.5% of the total variance. Geostatistical analyses, including the calculation of semivariogram parameters and model fitting, further confirmed the results of the statistical analysis. In the estimated maps of heavy metals, several hotspots of high metal concentrations were identified; Pb and Cu showed a very similar spatial pattern, indicating that they were likely from the same source. There is a clear heavy polluted hotspot of Pb, Cu, Zn, Cd and As in the northeast part of the Tiexi Industrial District because of the Shenyang Smelting Plant, which was a backbone enterprise of China's metallurgical industry. There were also hotspots for other heavy metals in other areas. This is mainly the result of the industrial processing that occurred in the study area. All of these data confirm that Pb, Cu, Zn, Cd and As are a result of anthropogenic activities, especially from industrial processes. For Cr and Mn, the concentration patterns indicate low spatial heterogeneity, with low correlation to other metals, indicating that the concentration of Cr and Mn are mainly caused by natural factors such as soil parent materials. Although the city government of Shenyang has placed a high priority on improving the environment in recent years, it will require a long time to completely eliminate pollution in this area.
► We investigated the contamination pattern of heavy metal in an industrial city. ► The soil contamination was spatially coupled with land use by GIS. ► Obvious heavy polluted hotspots were indentified for Pb, Cu, Zn, Cd and As. ► The contamination of Pb, Cu, Zn, Cd and As were caused anthropogenic activities. ► The concentrations of Cr and Mn mainly come from natural factors.
Display omitted
•A smart Br2-vapor-assisted CVD method is developed to fabricate CsPbBr3 PSCs.•Fast anion-exchange from CsPbI3 to CsPbBr3 is realized with the substitution of Br−.•Its structural ...stability is enhanced by means of crystal-lattice shrinking effect.•Air-stable and efficient CsPbBr3 all-inorganic PSCs is successfully achieved.•Our proprietary method opens a new avenue to solve the solubility issue of bromide.
Nowadays, inorganic perovskites such as CsPbI3 and CsPbBr3 with excellent photoelectric property and superior thermal stability have triggered strong interest in the photovoltaic community. However, all of the inorganic perovskite absorbers reported in literatures are fabricated by the complicated solution process. Meanwhile, CsPbI3 exists serious structural phase-transition; while stable CsPbBr3 suffers solubility limitation of bromide in conventional solution route. Herein, we develop a smart Br2-vapor-assisted chemical vapor deposition (CVD) method to realize the fast anion-exchange from CsPbI3 to CsPbBr3. With the substitution of small Br− anions, the undesirable phase-transition of CsPbI3 is heavily restrained and its structural stability is tremendously enhanced; and thus here we open a new avenue to solve the solubility issue of bromide. Consequently, CsPbBr3 all-inorganic perovskite solar cells (PSCs) with Carbon top electrode are first achieved by cost-effective CVD technology, showing a relatively high power conversion efficiency (PCE) of 5.38%. The charge transport mechanism of CsPbBr3 PSCs is correspondingly elucidated in-depth. We find that the interface of TiO2 and CsPbBr3 might be the root cause of hysteresis phenomenon, while another interface between Carbon and CsPbBr3 is not a rectifying contact but only increases the ohmic resistance of electrode. Moreover, our PSCs demonstrate a good long-term stability and give ∼90% of initial efficiencies after exposure to air for 21 days.
The purpose of this study is to investigate the current status of metal pollution of the sediments from urban-stream, estuary and Jinzhou Bay of the coastal industrial city, NE China. Forty surface ...sediment samples from river, estuary and bay and one sediment core from Jinzhou bay were collected and analyzed for heavy metal concentrations of Cu, Zn, Pb, Cd, Ni and Mn. The data reveals that there was a remarkable change in the contents of heavy metals among the sampling sediments, and all the mean values of heavy metal concentration were higher than the national guideline values of marine sediment quality of China (GB 18668-2002). This is one of the most polluted of the world's impacted coastal systems. Both the correlation analyses and geostatistical analyses showed that Cu, Zn, Pb and Cd have a very similar spatial pattern and come from the industrial activities, and the concentration of Mn mainly caused by natural factors. The estuary is the most polluted area with extremely high potential ecological risk; however the contamination decreased with distance seaward of the river estuary. This study clearly highlights the urgent need to make great efforts to control the industrial emission and the exceptionally severe heavy metal pollution in the coastal area, and the immediate measures should be carried out to minimize the rate of contamination, and extent of future pollution problems.
PDF
