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Withers-Martinez Chrislaine; Carpenter Elisabeth P.; Hackett Fiona; Ely Barry; Sajid Mohammed; Grainger Muni; Blackman Michael J. 《Protein engineering, design & selection : PEDS》1999,12(12):1113-1120
The A+T-rich genome of the human malaria parasite Plasmodiumfalciparum encodes genes of biological importance that cannotbe expressed efficiently in heterologous eukaryotic systems,owing to an extremely biased codon usage and the presence ofnumerous cryptic polyadenylation sites. In this work we haveoptimized an assembly polymerase chain reaction (PCR) methodfor the fast and extremely accurate synthesis of a 2.1 kb Plasmodiumfalciparum gene (pfsub-1) encoding a subtilisin-like protease.A total of 104 oligonucleotides, designed with the aid of dedicatedcomputer software, were assembled in a single-step PCR. Theassembly was then further amplified by PCR to produce a syntheticgene which has been cloned and successfully expressed in bothPichia pastoris and recombinant baculovirus-infected High FiveTMcells. We believe this strategy to be of special interest asit is simple, accessible and has no limitation with respectto the size of the gene to be synthesized. Used as a systematicapproach for the malarial genome or any other A + T-rich organism,the method allows the rapid synthesis of a nucleotide sequenceoptimized for expression in the system of choice and productionof sufficiently large amounts of biological material for completemolecular and structural characterization. 相似文献
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A widely recognized theme of construction economics suggests that the cost of construction per square meter increases as building height rises. However, over a number of years, research conducted regarding the height and cost issue has established a classic relationship between the two factors which can be represented by a U-shaped curve. This paper describes the study of the height-cost relationship of high-rise residential buildings in Shanghai in terms of the total construction cost and elemental costs while considering the context and commonality of buildings. This research was developed as an extension of the previous work, which examined data for buildings in Hong Kong. Initial findings indicate that the curves illustrating the relationships between height and cost of residential buildings in Shanghai and Hong Kong exhibit different profiles. The dissimilarities indicate that different sets of criteria should be applied in the judgment of height that affects cost in different locations. In terms of elemental costs, the findings suggest that there are differences in the way these costs react to changes in the building height. 相似文献
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Jillian M. Myers Jeremy P. Ramsey Alison L. Blackman A. Elizabeth Nichols Kevin P. C. Minbiole Reid N. Harris 《Journal of chemical ecology》2012,38(8):958-965
A powerful mechanism for protection against disease in animals is synergy between metabolites present in the natural microbiota of the host and antimicrobial peptides (AMPs) produced by the host. We studied this method of protection in amphibians in regard to the lethal disease chytridiomycosis, which is caused by Batrachochytrium dendrobatidis (Bd). In this study, we show that the AMPs of Rana muscosa, as well as the metabolite 2,4-diacetylphloroglucinol (2,4-DAPG) from Pseudomonas fluorescens, a bacterial species normally found on the skin of R. muscosa, were inhibitory to the growth of Bd in vitro. When both AMPs and 2,4-DAPG were used in growth inhibition assays, they worked synergistically to inhibit the growth of Bd. This synergy resulted in reduced minimum concentrations necessary for inhibition by either 2,4-DAPG or AMPs. This inhibitory concentration of AMPs did not inhibit the growth of a P. fluorescens strain that produced 2,4-DAPG in vitro, although its growth was inhibited at higher peptide concentrations. These data suggest that the AMPs secreted onto frog skin and the metabolites secreted by the resident beneficial bacteria may work synergistically to enhance protection against Bd infection on amphibian skin. These results may aid conservation efforts to augment amphibian skins’ resistance to chytridiomycosis by introducing anti-Bd bacterial species that work synergistically with amphibian AMPs. 相似文献
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