同步辐射CD分析Gd@C_(82)(OH)_(22)纳米颗粒对λ-DNA结构稳定性的影响  

SRCD study on stability of λ-DNA by Gd@C_(82)(OH)_(22) nanoparticles

作　　者：宋炎[1,2] 葛永辉[2,3] 崔素霞[1] 

机构地区：[1]首都师范大学,北京100048 [2]中国科学院高能物理研究所,北京100049 [3]北京理工大学,北京100081

出　　处：《核技术》2011年第2期129-133,共5页Nuclear Techniques

基　　金：国家自然科学基金(10875135);科技部国家重点基础研究发展计划(2009CB930204)资助

摘　　要：本文利用同步辐射真空紫外圆二色光谱(SRCD)研究λ噬菌体DNA(λ-DNA)加入内包金属富勒烯Gd@C82(OH)22纳米颗粒后的二级结构变化,推测了纳米颗粒与λ-DNA相互作用机理。研究发现,在SRCD 230–255 nm波长范围内,λ-DNA经Gd@C82(OH)22纳米颗粒处理后,在245 nm处的负峰减弱并伴随DNA熔解温度(Tm值)降低。说明λ-DNA及λ-DNA酶切片段受Gd@C82(OH)22纳米颗粒影响,导致二级结构稳定性和热稳定性下降。通过分析SRCD谱在180–200 nm处的信息,发现Gd@C82(OH)22纳米颗粒引起了λ-DNA超螺旋结构的解旋。Circular dichroism spectroscopy is widely used to studies the secondary structures of protein and DNA, and identify the interaction of the biomolecules. In this work, we analyzed the SRCD spectra between 230-255 nm and found that the Gd@C82（OH）22 fullerene nanoparticles were capable of affecting the secondary structure of λ-DNA and λ-DNA HindIII. We also tested the melting temperature （Tm） of both kinds of DNA, and found that after treated with Gd@C82（OH）22 nanoparticles both of the Tm values decreased significantly. By analyzing SRCD spectra between 180-200 nm we found that the information of DNA supercoil structure could be obtained. The results show that Gd@C82（OH）22 nanoparticles can affect the secondary structure and thermostability of λ-DNA and λ-DNA HindIII, and the λ-DNA supercoil structure as well.

关 键 词：λ-DNA Gd@C82(OH)22 SRCD DNA二级结构 DNA超螺旋 

分 类 号：Q945.79[生物学—植物学]