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991.
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Hai-Bin Dai Miao-Miao Xu Jia Lv Xiang-Jun Ji Si-Hai Zhu Ru-Meng Ma Xiao-Lei Miao Man-Lin Duan 《Molecular neurobiology》2016,53(7):4865-4873
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This study aimed to improve understanding of the strategies developed by the Mediterranean seaweed Taonia atomaria to chemically control bacterial epibiosis. An experimental protocol was optimized to specifically extract algal surface-associated metabolites by a technique involving dipping in organic solvents whilst the integrity of algal cell membranes was assessed by fluorescent microscopy. This methodology was validated using mass spectrometry-based profiles of algal extracts and analysis of their principal components, which led to the selection of methanol as the extraction solvent with a maximum exposure time of 15 s. Six compounds (A–F) were identified in the resulting surface extracts. Two of these surface-associated compounds (B and C) showed selective anti-adhesion properties against reference bacterial strains isolated from artificial surfaces while remaining inactive against epibiotic bacteria of T. atomaria. Such specificity was not observed for commercial antifouling biocides and other molecules identified in the surface or whole-cell extracts of T. atomaria. 相似文献
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Lipase‐Catalyzed Kinetic Resolution of Novel Antifungal N‐Substituted Benzimidazole Derivatives 下载免费PDF全文
Edyta Łukowska‐Chojnacka Monika Staniszewska Małgorzata Bondaryk Jan K. Maurin Maria Bretner 《Chirality》2016,28(4):347-354
A series of new N‐substituted benzimidazole derivatives was synthesized and their antifungal activity against Candida albicans was evaluated. The chemical step included synthesis of appropriate ketones containing benzimidazole ring, reduction of ketones to the racemic alcohols, and acetylation of alcohols to the esters. All benzimidazole derivatives were obtained with satisfactory yields and in relatively short times. All synthesized compounds exhibit significant antifungal activity against Candida albicans 900028 ATCC (% cell inhibition at 0.25 μg concentration > 98%). Additionally, racemic mixtures of alcohols were separated by lipase‐catalyzed kinetic resolution. In the enzymatic step a transesterification reaction was applied and the influence of a lipase type and solvent on the enantioselectivity of the reaction was studied. The most selective enzymes were Novozyme SP 435 and lipase Amano AK from Pseudomonas fluorescens (E > 100). Chirality 28:347–354, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
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Xiulian Zhang Yasuhiro Kuramitsu Aiguo Ma Hui Zhang Kazuyuki Nakamura 《Cytotechnology》2016,68(4):1103-1113
Proteomic study on membrane-integrated proteins in endoplasmic reticulum (ER) fractions was performed. In this study, we examined the effects of heat stress on Jurkat cells. The ER fractions were highly purified by differential centrifugation with sodium carbonate washing and acetone methanol precipitations. The ER membrane proteins were separated by one dimensional electrophoresis (1-DE), and some of the protein bands changed their abundance by heat stress, 12 of the 14 bands containing 40 and 60 ribosomal proteins whose expression level were decreased, on the contrary, 2 of the 14 bands containing ubiquitin and eukaryotic translation initiation factor 3 were increased. Heat treatment of human Jurkat cells led to an increase in the phosphorylation of PERK and eIF2α within 30 min of exposure. This was followed by an increase in the expression of the GRP78. Protein ubiquitination and subsequent degradation by the proteasome are important mechanisms regulating cell cycle, growth and differentiation, the result showed that heat stress enhanced ubiquitination modification of the microsomal proteins. The data of this study strongly suggest that heat treatment led to a significant reduction in protein expression and activated UPR, concomitant with protein hyperubiqutination in ER. 相似文献