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Cells adhesion is very important for many physiological processes. Using advanced Raman microspectroscopic technique, we selected T Leukemia cells (Jurkat) as the materials and obtained simultaneously conformation information of various biomolecules inside the whole living cells. By comparing the Raman microspectroscopic spectra of single and adhesive cancer cells, we found for the first time that when cells adhered, the conformation of the biomolecules (DNA, protein, carbohydrates and lipids) inside the cells had different changes: (i) the backbone of double-stranded DNA maintained orderly B-form or modified B-form conformation, whereas the groups of its deoxyribose and bases were modified; (ii) the conformational changes of the main chain and the side chain in the protein were obviously variant. The lines intensity belonging to a-helix and p-sheet decreased, while that of p-turn increased. Tyrosine and tryptophane residues of the protein changed from "buried state" to "exposed state"; the lines intensi 相似文献
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Hypocrellabambusae(B.etBr)Sacc.,onekindoffungus,isparasitizedontheSinarundinariasp.ItgrowsabundantlyinthenorthwesternregionofYunnanProvinceofChina,andhasalonghistoryofworkingasatraditionalmedicinalagent[1].Itspromisinganticancerandantiviralfunctionshaveled… 相似文献
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黏附细胞中生物大分子结构变化的显微Raman光谱 总被引:1,自引:0,他引:1
鉴于细胞黏附作用的重要生物学意义, 选择了T淋巴细胞(Jurkat)为实验对象, 用先进的显微Raman光谱技术, 同时获得用其他方法难以得到的活细胞内数种生物大分子的构象信息. 通过比较单个和黏附细胞的显微Raman光谱的差异发现, 当细胞黏附时, 细胞内生物分子(DNA, 蛋白质, 碳水化合物, 脂类)的构象有不同的变化: (ⅰ) 双链DNA的骨架保持有序的B型或修改的B型构象, 然而它的脱氧核糖和碱基(A, G, C, T)的一些基团被修饰. (ⅱ) 蛋白质构象的主、侧链变化明显不同, 属于a螺旋和b折叠的一些谱线强度下降而b回折的一些谱线强度却明显增加; 酪氨酸和色氨酸从“埋藏状态”变成“暴露状态”; 它的巯基基团的谱线强度也有增加; 二硫键的构象从两种变成3种, 表明细胞黏附引起该蛋白质主链的氢键体系和侧链环境的变化. (ⅲ) 碳水化合物的一些基团同时被修饰. (ⅳ) 膜脂双层的构象变化很明显, 随着黏附细胞数目的增加, 链间侧向相互作用序参数逐渐减少, 提示细胞黏附导致细胞膜的流动性和离子通透性增加. 相似文献
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竹红菌乙素敏化的人红细胞膜结构光损伤的Raman光谱特征 总被引:2,自引:0,他引:2
采用Raman光谱从分子水平揭示了竹红菌乙素光敏损伤的人红细胞膜发生膜蛋白交联和膜脂脂质过氧化导致其功能变化 ;膜流动性和离子通透性增加的本质是竹红菌乙素产生的活性氧 ( 1O2 ,O2 -·和·OH等 )破坏了红细胞膜的有序结构 ,使膜蛋白主链结构的α 螺旋、β 折叠明显减少 ,无规卷曲增加并使其侧链结构的巯基基团、吲哚环、对羟苯基环、单基取代苯基环等也明显减少 .与此同时 ,随着光照时间的增加 ,膜脂的反式构象呈先增加后减少的趋势 ,它的扭曲构象则正好相反 .膜蛋白和膜脂构象不灵敏的CH2 和CH3弯曲振动谱线的明显下降 ,揭示它们有链的断裂 . 相似文献
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人类免疫缺损病毒(HIV)的空间结构及金丝桃蒽酮素诱导的HIV光敏损伤的Raman光谱研究 总被引:7,自引:0,他引:7
获得了人血清中的HIV1—HIV2及金丝桃蒽酮素诱导的该病毒光敏损伤的Raman光谱. 其中突出的谱线指定为病毒糖蛋白的碳水化合物, RNA, 蛋白质和类脂. HIV1—HIV2的Raman光谱受控于组分碳水化合物的Raman散射. 它的碳水化合物中D-甘露糖和N-乙酰基葡萄糖的谱线非常明显, 并且D-甘露糖的异头Cl位存在着β构型, 结合的病毒RNA双螺旋呈A型构象. 病毒RNA的骨架磷酸基团、核糖和碱基(包括碱基之间氢键)的谱线完整、清晰, 病毒蛋白质的二级结构有α-螺旋、β-折叠、β-回折和无规卷曲, 它的侧链丰富、多彩, 有色氨酸、苯丙氨酸和“埋藏的”酪氨酸, 有稳定的具有扭曲-扭曲-扭曲构象的二硫键和具有扭曲、反式二种构象的碳硫键, 还有巯基、离子化和非离子化的羧基等. 病毒的脂双层分子可能处于有序的液晶相或凝胶相. 金丝桃蒽酮素诱导人类免疫缺损病毒(HIV1—HIV2)的光敏损伤, 使该病毒的各个组分发生了不同程度的变化, 有序的A型RNA变为无序, 它的垂直的碱基-碱基相互作用被破坏, 并有碱基之间氢键的断裂. 此外, 核糖和4个碱基的一些基团有明显的损伤. 与此同时, 病毒蛋白质的有序结构(α-螺旋和β-折叠)减少, 无规卷曲增加, 反式C—S键有较强的损伤. 埋藏在蛋白质三维结构中的酪氨酸虽然有损伤, 但仍是“埋藏的”. 属于病毒包膜糖蛋白的碳水化合物, 包括D-甘露糖和N-乙酰基葡萄糖的一些基团有一些变化. 病毒类脂中亲水的胆碱C—N基团也有损伤, 它可能是金丝桃蒽酮素与类脂的结合地点, 然而该脂双层可能仍处于有序的液晶相或凝胶相. 因此, 在本实验条件下, 人类免疫缺损病毒HIV1—HIV2的空间结构有一些损伤, 这些损伤可能会阻断病毒的传染, 遏制它的发育和繁殖. 激光Raman光谱从分子水平提供了HIV1—HIV2的空间结构光敏损伤的某些直接的证据. 相似文献
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Aspecialdyestuffwaschosenandmadetobeabsorbedbythecellsoftumor,andthenthecellswereirradiatedunderalaserbeamwithacertainwavelengthinordertocurecancer.Thisisknownaslaserchemicaltherapy.Althoughphotosensitizationhasbeendevelopedintheearly20thcenturyandanum… 相似文献
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Hypocrellinanditsderivativesarewellknownphotosensitizers[1,2].AmongthembothhypocrellinA(HA)andhypocrellinB(HB)showpromisinganticancerandantiviralability[1—3].Inordertoinvestigateitsmechanisms,manymethodshavebeenusedtodetecttheactiveoxygensuchas1O2,O2.-,.OHandsem… 相似文献
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Cells adhesion is very important for many physiological processes. Using advanced Raman microspectroscopic technique, we selected T Leukemia cells (Jurkat) as the materials and obtained simultaneously conformation information of various biomolecules inside the whole living cells. By comparing the Raman microspectroscopic spectra of single and adhesive cancer cells, we found for the first time that when cells adhered, the conformation of the biomolecules (DNA, protein, carbohydrates and lipids) inside the cells had different changes: (i) the backbone of double-stranded DNA maintained orderly B-form or modified B-form conformation, whereas the groups of its deoxyribose and bases were modified; (ii) the conformational changes of the main chain and the side chain in the protein were obviously variant. The lines intensity belonging to α-helix and β-sheet decreased, while that of β-turn increased. Tyrosine and tryptophane residues of the protein changed from “buried state” to “exposed state”; the lines intensity of its sulfhydryl group also increased; the conformation of its disulfide bond changed from two kinds to three kinds. These facts suggest that the cells adhesion causes changes in H-bonds organization of the main chain and environment of the side chain in the protein; (iii) the groups of the carbohydrates were also modified simultaneously; (iv) the conformation of the lipids bilayers of the membranes changed obviously; the order parameter for lateral interaction between chains decreased gradually with the increase of number of the adhesive cells. So cells adhesion resulted in an increase in fluidity of the membrane and ion permeability on the membrane. 相似文献