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61.
在肽库中进行小肽筛选的初步研究   总被引:1,自引:0,他引:1  
齐杰  方锐 《高等学校化学学报》1996,17(11):1738-1741
以合成六肽DGGSAA为模型对在噬菌体肽库中进行小肽筛选做了初步研究。结果表明,含有可形成氢键和离子键残基的小肽能够在噬菌体肽库中进行筛选。并用明显提高了筛选的专一性。  相似文献   
62.
Natural products from the human microbiota may mediate host health and disease. However, discovery of the biosynthetic gene clusters that generate these metabolites has far outpaced identification of the molecules themselves. Here, we used an isolation-independent approach to access the probable products of a nonribosomal peptide synthetase-encoding gene cluster from Ruminococcus bromii, an abundant gut commensal bacterium. By combining bioinformatics with in vitro biochemical characterization of biosynthetic enzymes, we predicted that this pathway likely generates an N-acylated dipeptide aldehyde (ruminopeptin). We then used chemical synthesis to access putative ruminopeptin scaffolds. Several of these compounds inhibited Staphylococcus aureus endoproteinase GluC (SspA/V8 protease). Homologs of this protease are found in gut commensals and opportunistic pathogens as well as human gut metagenomes. Overall, this work reveals the utility of isolation-independent approaches for rapidly accessing bioactive compounds and highlights a potential role for gut microbial natural products in targeting gut microbial proteases.  相似文献   
63.
Stellatolide H (1) was isolated from a deep-sea sponge Discodermia sp. as the cytotoxic constituent. The planar structure of 1 was elucidated on the basis of the NMR spectroscopic and mass spectrometric data. The absolute configurations of the constituent amino acid residues were determined by the Marfey’s method. Stellatolide H (1) is a peptide lactone of the callipeltin class with its N-terminus blocked by 3-hydroxy-6,8-dimethyldeca-(4Z,6E)-dienoic acid (Hdda).  相似文献   
64.
A novel kind of inorganic-organic hybrid supramolecular hydrogel with excellent anti-biofouling capability was developed. The hydrogel was formed via ionic interaction between the negative-charged sodium polyacrylate (SPA) entwined clay nanosheets (CNS) and positive-charged polyhedral oligomeric silsesquioxane (POSS) core-based generation one (L-Arginine) dendrimer (POSS-R).  相似文献   
65.
An enantioselective approach to substituted indolizidine and quinolizidine frameworks has been developed. Key steps of the synthesis are the enantioselective, palladium-catalyzed N-allylation of an imide, the nucleophilic allylation of an acyliminium ion and a ring closing metathesis. This general strategy has been applied to the synthesis of indolizidine peptide mimics, starting from a chiral imide derived from l-aspartic acid. It was observed that the preexisting stereogenic center of this substrate has a moderate influence on the stereoselectivity of the electrophilic allylation, which is mainly determined by the sense of chirality of the catalyst.  相似文献   
66.
Photosensitive supramolecular peptide hydrogels with the gelators forming by the integration of photosensitive moieties and peptides have been briefly summarized the hydrogelation capabilities, the expressing manner serving as smart materials, and practical applications.  相似文献   
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钙调素 ( Ca M)存在于所有真核细胞生物体内 ,它可与很多天然的生物活性肽结合 ,如 β-内啡肽、胰高血糖素和某些昆虫毒液肽等 [1] .有关 Ca M与多肽相互作用的研究普遍认为 ,对 Ca M有高亲和性的多肽应该具有形成α螺旋结构的显著倾向[2 ] .为进一步确认多肽的主链构象对 Ca M亲和能力的影响 ,我们采用圆二色性光谱和核磁共振波谱分析了荞麦花粉碱性十二肽 BPP-1和它的类似物 BPP-3的结构特征 ,配合多肽对花粉钙调素 ( p Ca M)的结合能力 ,发现肽链的可塑性和 C端的极性是影响多肽与 p Ca M亲和能力的因素 ,而形成 α螺旋结构的倾…  相似文献   
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A new cyclic pentapeptide and three new linear peptides, namely, aspergillipeptides D–G (14), were isolated from a culture broth of marine gorgonian-derived fungus Aspergillus sp. SCSIO 41501. Their structures were elucidated by spectroscopic analysis, and their absolute configurations were confirmed by Marfey’s method. Compounds 1 and 2 showed evident antiviral activity against herpes simplex virus type 1 (HSV-1) with IC50 values of 9.5 and 19.8 µM under their non-cytotoxic concentrations against a Vero cell line, respectively, and 1 also had antiviral activity against acyclovir-resistant clinical isolates of HSV-1.  相似文献   
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