排序方式: 共有125条查询结果,搜索用时 125 毫秒
41.
《Analytical letters》2012,45(13):2029-2039
A novel platform for detection of histone deacetylase (HDAC) activity has been developed using a gold nanoparticle based fluorescence resonance energy transfer (FRET) immunoassay. This strategy combined the acetylated fluorescent peptide probe with the anti-acetyl antibody functionalized Au NPs to measure the deacetylation activity of histone deacetylase sirtuin2. Enzymatic deacetylation of the acetylated peptide substrate was detected by a gold nanoparticle labeled anti-acetyl peptide antibody with the formation of the immunocomplex resulting in energy transfer between the fluorescent dyes and the nanoparticles. Due to the highly efficient fluorescence quenching of the gold nanoparticles, the proposed method shows a low background and favorable sensitivity. In addition, this approach can be applied to the evaluation of HDAC inhibitor activity. The proposed platform should facilitate the development of new assays for HDAC activity and other histone modifications. 相似文献
42.
组蛋白去乙酰化酶抑制剂是一类以组蛋白去乙酰化酶为靶点的新型靶向抗肿瘤药物,在抗增殖、促凋亡、促分化、阻滞细胞生长周期、抗血管生成等方面有很好的作用。组蛋白去乙酰化酶抑制剂以其独特的抗肿瘤作用机理,在研发肿瘤治疗药物中占有重要地位。在组蛋白去乙酰化酶抑制剂分类中,环肽类抑制剂结构最为复杂,对多种类型的实体瘤及血液学癌细胞均具有良好的对抗作用。本文针对天然和化学合成的环肽类组蛋白去乙酰化酶抑制剂中金属结合区、表面识别区以及连接区的结构特点进行了综述,并描述了各类抑制剂对酶的抑制活性和抗肿瘤增殖活性。对抑制剂不同结构区的修饰、改造可以使抑制剂对不同肿瘤细胞具有高效性和特异性作用,通过构效关系研究寻找具有高效低毒、靶向性环肽类抑制剂的结构规律,可为研究开发抗肿瘤药物提供帮助。 相似文献
43.
提出了一种组蛋白乙酰化修饰检测的耦合增强拉曼散射生物传感新方法. 该方法以金纳米粒子为表面增强拉曼散射(SERS)基底, 表面修饰乙酰化组蛋白H3多肽为识别探针, 对甲氧基苯硫酚(4-MTP)为拉曼标记物, 制备了组蛋白乙酰化修饰检测的SERS纳米探针. 通过紫外可见吸收光谱与动态光散射分析, 证实了组蛋白乙酰化抗体可介导SERS纳米粒子发生可控组装与聚集, 使SERS纳米探针间发生局域电场共振耦合, 产生显著增强的SERS信号. 基于此, 通过待测抗原与SERS纳米探针对抗体的竞争性相互作用, 我们设计了组蛋白乙酰化修饰检测的竞争免疫SERS生物传感方法. 该法操作简便、快速、重现性好, 且裸眼即能进行可视化鉴定. 通过设计不同染料标记的SERS纳米探针, 该法有望实现多种组蛋白修饰的复合检测. 相似文献
44.
Koichi Narita Takuya Kikuchi Kazuhiro Watanabe Dr. Toshiya Takizawa Dr. Takamasa Oguchi Dr. Kyosuke Kudo Keisuke Matsuhara Hideki Abe Dr. Takao Yamori Prof. Dr. Minoru Yoshida Prof. Dr. Tadashi Katoh Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(42):11174-11186
The bicyclic depsipeptide histone deacetylase (HDAC) inhibitors spiruchostatins A and B, 5′′‐epi‐spiruchostatin B and FK228 were efficiently synthesized in a convergent and unified manner. The synthetic method involved the following crucial steps: i) a Julia–Kocienski olefination of a 1,3‐propanediol‐derived sulfone and a L ‐ or D ‐malic acid‐derived aldehyde to access the most synthetically challenging unit, (3S or 3R,4E)‐3‐hydroxy‐7‐mercaptohept‐4‐enoic acid, present in a D ‐alanine‐ or D ‐valine‐containing segment; ii) a condensation of a D ‐valine‐D ‐cysteine‐ or D ‐allo‐isoleucine‐D ‐cysteine‐containing segment with a D ‐alanine‐ or D ‐valine‐containing segment to directly assemble the corresponding seco‐acids; and iii) a macrocyclization of a seco‐acid using the Shiina method or the Mitsunobu method to construct the requisite 15‐ or 16‐membered macrolactone. The present synthesis has established the C5′′ stereochemistry of spiruchostatin B. In addition, HDAC inhibitory assay and the cell‐growth inhibition analysis of the synthesized depsipeptides determined the order of their potency and revealed some novel aspects of structure–activity relationships. It was also found that unnatural 5′′‐epi‐spiruchostatin B shows extremely high selectivity (ca. 1600‐fold) for class I HDAC1 (IC50=2.4 nM ) over class II HDAC6 (IC50=3900 nM ) with potent cell‐growth‐inhibitory activity at nanomolar levels of IC50 values. 相似文献
45.
Małgorzata M. Jaworska Jolanta Bryjak Jolanta Liesiene 《Cellulose (London, England)》2009,16(2):261-270
Chitin deacetylase is an enzyme that can play an important role in enzymatic deacetylation of chitosan to obtain polymers
with a lower degree of acetylation. As this enzyme has never been immobilized up to now, efforts were directed towards determining
both the most suitable carrier and the best method of covalent attachment to the selected carrier. In the preliminary experiments
several different carriers were tested that were based on acrylic, silica-gel, agarose, dextran or cellulose materials. The
best results were obtained for cellulose-based Granocel matrix. DEAE- and NH2-Granocel activated with divinyl sulfone or glutaraldehyde were chosen for optimization of the immobilization procedure and
the carrier’s superstructure. It was found that covalent binding of chitin deacetylase on DEAE-Granocel-2000 via divinyl sulfone
offers preparations with the highest activity and stability. The characteristics of the selected preparation and comparison
with the native enzyme show that optimal conditions are close to those for the free enzyme: the optimal pH is 4.0 for both
enzymes and the optimal temperatures are 55 °C and 50 °C for native and immobilized forms, respectively. The kinetics of chitosan
deacetylation for both enzymes follow the Michaelis–Menten relationship, but significant differences in the values of the
equation parameters were observed. 相似文献
46.
以MS-275为先导化合物,设计并合成了7个新型苯甲酰胺类化合物(6a~6c, 14a, 14b, 15a和18),其结构经1H NMR和ESI-MS表征。采用MTT法测定了6a~6c, 14a, 14b, 15a和18对人急性白血病细胞(HL60)和人乳腺癌细胞(MCF-7)的体外抗肿瘤细胞增殖活性。结果表明:N-(2-氨基苯)-3-[4-(吡啶-3-基)嘧啶-2-氨基]己酰胺(6a), N-(2-氨基苯)-4-【3-{4-[(二乙胺基)甲基]苯基}丙烯酰】苯甲酰胺(14a)和N-(2-氨基苯)-4-[3-(吡啶-3-基)丙烯酰]丙酰胺(18)的抑制活性较好,其GI50依次为5.72 μmol·L-1, 6.91 μmol·L-1, 7.11 μmol·L-1和3.46 μmol·L-1, 4.12 μmol·L-1, 3.97 μmol·L-1,优于MS-275(7.88 μmol·L-1和4.49 μmol·L-1)。 相似文献
47.
48.
利用分子梳技术对λ DNA和组蛋白的相互作用进行了研究. 通过这种简单有效的方法,我们将λ DNA分子拉伸到26—28 μm,相当于其原长(约162 μm)的16—17倍. 当组蛋白与DNA结合后,DNA分子发生凝聚现象,复合体的拉伸长度明显变短,其峰值分布在10—14 μm之间. DNA 组蛋白复合体的拉伸长度与组蛋白的浓度、与碱基对和荧光染料的比例有显著的关系.
关键词:
分子梳
组蛋白
DNA
荧光显微 相似文献
49.
脱氧核糖核酸 (DNA)和蛋白质是构成生命体最为重要的两类生物大分子 .随着科学技术的快速发展 ,越来越多的纳米技术被用来研究这些生物大分子 .文章详细介绍了近来利用纳米孔技术研究DNA的一些进展 .结合作者近期利用聚焦离子束 (FIB)制作纳米孔的工作 ,提出了利用纳米孔解离核小体的设想 .如果能够利用纳米孔将双螺旋DNA从组蛋白八聚体上剥离下来 ,并探测这一过程 ,将揭示核小体中包含的许多生物化学、物理信息 .文章对此进行了较为详细的分析 :处于电场中的核小体在电场的作用下 ,DNA分子穿越纳米孔 ,同时由于纳米孔的阻挡力 ,使组蛋白不能穿越 ,从而诱使DNA从组蛋白八聚体上分离下来 .通过准确检测DNA分子穿孔过程中引起的电流阻塞效应 ,可将DNA与组蛋白的相互作用的一些性质反映出来 相似文献
50.