二价金属离子对鲑鱼精DNA热稳定性的影响  

The Effects of Divalent Metal Ions on the Thermal Stability of Salmon Sperm DNA

作　　者：邬瑞光[1] 尉志武[1] 陈琳[1] 周蕊[1] 

机构地区：[1]清华大学化学系,生命有机磷化学与化学生物学教育部重点实验室,北京100084

出　　处：《高等学校化学学报》2002年第12期2366-2368,共3页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金 (批准号 :2 99730 19;2 0 1330 30 );留学回国人员基金资助

摘　　要：The effects of Mg 2+, Ca 2+, Mn 2+, Co 2+ and Ni 2+ on the thermal stability of Salmon Sperm DNA were investigated by employing differential scanning calorimetry method. For the divalent cations, the shielding effect plays the dominant role in the interaction of nucleic acid chains when they are in low concentrations, as reflected in the moderate increasing of DNA melting temperature. Along with increasing concentration, both alkaline earth metal ions and transitional metal ions were found to lower the DNA melting temperature, indicating possible direct interaction between the divalent cations with the bases in the DNA molecules. The effectiveness increases with the order Mg 2+, Ca 2+, Mn 2+, Co 2+ and Ni 2+. It was found for the first time that the presence of Mn 2+ triggered the biphasic-melting behavior of the Salmon Sperm DNA when the concentration of the cation was increased to a value about 2 times of phosphorous in DNA.The effects of Mg 2+, Ca 2+, Mn 2+, Co 2+ and Ni 2+ on the thermal stability of Salmon Sperm DNA were investigated by employing differential scanning calorimetry method. For the divalent cations, the shielding effect plays the dominant role in the interaction of nucleic acid chains when they are in low concentrations, as reflected in the moderate increasing of DNA melting temperature. Along with increasing concentration, both alkaline earth metal ions and transitional metal ions were found to lower the DNA melting temperature, indicating possible direct interaction between the divalent cations with the bases in the DNA molecules. The effectiveness increases with the order Mg 2+, Ca 2+, Mn 2+, Co 2+ and Ni 2+. It was found for the first time that the presence of Mn 2+ triggered the biphasic-melting behavior of the Salmon Sperm DNA when the concentration of the cation was increased to a value about 2 times of phosphorous in DNA.

关 键 词：鲑鱼精DNA 热稳定性 二价金属离子 两阶段熔解行为 DSC 

分 类 号：Q523[生物学—生物化学]