Tb^(3+)离子发光探针研究Ca^(2+),La^(3+)和Al^(3+)与拟南芥钙调素的竞争结合  

Investigation on Competition Binding of Ca^(2+), La^(3+) and Al^(3+) to Tb_4^(3+)·CaM System by Using Tb^(3+) Fluorescence Probes

作　　者：肖凤娟[1] 刘德龙[2] 白娟[3] 孙大业[3] 

机构地区：[1]石家庄铁道学院材料分院,河北石家庄050043 [2]河北师范大学化学学院,河北石家庄050091 [3]河北师范大学生命科学学院,河北石家庄050091

出　　处：《中国稀土学报》2004年第3期408-411,共4页Journal of the Chinese Society of Rare Earths

基　　金：国家自然科学基金重点项目 ( 3 973 0 2 3 0 ) ;河北省博士基金资助项目

摘　　要：利用Tb3+ 离子的发光 ,研究了Tb3+ 与拟南芥钙调素 (CaM )结合的荧光光谱及荧光滴定曲线特点 ,然后利用Tb3+ 4·CaM系统在 2 2 1nm直接激发和 2 80nm敏化激发的光谱变化研究了Ca2 + ,La3+ 和Al3+ 与拟南芥钙调素 (CaM )的竞争结合作用。结果表明 :Tb3+ ,La3+ 与钙调素的竞争结合能力强于Ca2 + ,而Tb3+的竞争结合力又大于La3+ ,Ca2 +与钙调素的结合力远大于Al3+。竞争实验的结果从分子水平上揭示了Tb3+ ,La3+ 和Al3+ 等金属离子生物效应可能的分子机制。The binding properties of Tb^(3+) to CaM were studied by using directly excited Tb^(3+) fluorescence (λ_(ex)=221 nm) and CaM-tyrosine sensitized Tb^(3+) fluorescence (λ_(ex)=280 nm). The competition effects of metal ions Ca^(2+), La^(3+) and Al^(3+)on Tb^(3+)_4·CaM system were tested by Tb^(3+) fluorescence probe. The competition binding abilities of Tb^(3+) and La^(3+) to CaM are higher than that of Ca^(2+), and the affinity of Ca^(2+) to CaM is higher than that of Al^(3+). The results comfirm that RE ions can substitute Ca^(2+) in Ca^(2+)_4·CaM system and bind to calmodulin competively,and this may be the molecular mechanism of the biological effects of Tb^(3+), La^(3+) and Al^(3+).

关 键 词：生物无机化学 Tb^3+离子发光探针 CA^2+ LA^3+ AL^3+ 稀土 

分 类 号：O657.3[理学—分析化学]