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Dr. Alexander J. M. Disney Prof. Barrie Kellam Dr. Lodewijk V. Dekker 《ChemMedChem》2016,11(9):972-979
The natural product staurosporine is a high‐affinity inhibitor of nearly all mammalian protein kinases. The labelling of staurosporine has proven effective as a means of generating protein kinase research tools. Most tools have been generated by acylation of the 4′‐methylamine of the sugar moiety of staurosporine. Herein we describe the alkylation of this group as a first step to generate a fluorescently labelled staurosporine. Following alkylation, a polyethylene glycol linker was installed, allowing subsequent attachment of fluorescein. We report that this fluorescein–staurosporine conjugate binds to cAMP‐dependent protein kinase in the nanomolar range. Furthermore, its binding can be antagonised with unmodified staurosporine as well as ATP, indicating it targets the ATP binding site in a similar fashion to native staurosporine. This reagent has potential application as a screening tool for protein kinases of interest. 相似文献
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利用有机化工废水培养基从新疆高海拔盐湖样品中分离筛选到COD降解菌18株,对COD降解率高的8株菌株混合后处理废水,与其他普通活性污泥相比,COD去除率更高(86.3%)。经16S r DNA初步鉴定,该8株菌分别属于拟杆菌门Bacteroidetes、厚壁菌门Firmicutes和变形菌门Proteobacteria。将该混合菌群用于生物曝气池试验,添加尿素0.75 g/L作为氮源,其COD降解率可达82.5%;添加金枪鱼蛋白胨0.5 g/L可使COD降解率提高到92.2%。 相似文献
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Andrews MJ Kontopidis G McInnes C Plater A Innes L Cowan A Jewsbury P Fischer PM 《Chembiochem : a European journal of chemical biology》2006,7(12):1909-1915
We describe a drug-design strategy termed REPLACE (REplacement with Partial Ligand Alternatives through Computational Enrichment) in which nonpeptidic surrogates for specific determinants of known peptide ligands are identified in silico by using a core peptide-bound protein structure as a design anchor. In the REPLACE application example, we present the effective replacement of two critical binding motifs in a lead protein-protein interaction inhibitor pentapeptide with more druglike phenyltriazole and diphenyl ether groups. These were identified through docking of fragment libraries into the volume of the cyclin-binding groove of CDK2/cyclin A vacated through truncation of the inhibitor peptide-binding determinants. Proof of concept for this strategy was obtained through the generation of potent peptide-small-molecule hybrids and by the confirmation of inhibitor-binding modes in X-ray crystal structures. This method therefore allows nonpeptide fragments to be identified without the requirement for a high-sensitivity binding assay and should be generally applicable in replacing amino acids as individual residues or groups in peptide inhibitors to generate pharmaceutically acceptable lead molecules. 相似文献
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生物絮凝剂产生菌的筛选及絮凝处理靛蓝印染废水的研究 总被引:1,自引:0,他引:1
从活性污泥中分离出22株菌株,筛选得到具有絮凝活性的菌株14株,其中FJ-7、FJ-15絮凝活性较高。将两株絮凝剂产生菌分别纯培养及以体积比1∶1比例混合培养,发现混合培养发酵液对高岭土悬浊液的絮凝效果优于各菌株的纯培养发酵液。利用此混合发酵液对靛蓝印染废水进行絮凝处理,考察了生物絮凝剂和助凝剂CaC l2的用量、废水pH对脱色效果的影响。在混合菌发酵液和助凝剂CaC l2的体积分数分别为5%和4%、废水pH=8.0的最适脱色条件下,混合发酵液对靛蓝废水的脱色率可达87.2%。 相似文献
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Amyloid beta peptide (Abeta) fibril formation is widely believed to be the causative event of Alzheimer's disease pathogenesis. Therapeutic approaches are therefore in development that target various sites in the production and aggregation of Abeta. Herein we present a high-throughput screening tool to generate novel hit compounds that block Abeta fibril formation. This tool is an application for our fibril model (Abeta(16-37)Y(20)K(22)K(24))(4), which is a covalent assembly of four Abeta fragments. With this tool, screening studies are complete within one hour, as opposed to days with native Abeta(1-40). A Z' factor of 0.84+/-0.03 was determined for fibril formation and inhibition, followed by the reporter molecule thioflavin T. Herein we also describe the analysis of a broad range of reported inhibitors and non-inhibitors of Abeta fibril formation to test the validity of the system. 相似文献
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