摘要
本文用荧光光谱法研究了皖南尖吻蝮蛇毒糖苷水解酶（ＮＡＤａｓｅ）的性质。在ｐＨ＜６时，ｐＨ对ＮＡＤａｓｅ的荧光强度影响较大，而在ｐＨ＞６，ｐＨ对ＮＡＤａｓｅ的荧光强度几乎没有什么影响，Ｃｕ２＋的加入可引起ＮＡＤａｓｅ的内源荧光强度的降低，通过荧光滴定测得Ｃｕ２＋与ＮＡＤａｓｅ结合常数ＫＥＭ为５．３×１０３（ｍｏｌ／Ｌ）－１。Ｉ－对ＮＡＤａｓｅ发光的淬灭作用很小，Ｉ－浓度为０．１ｍｏｌ／Ｌ和０．２ｍｏｌ／Ｌ时仅分别能淬灭为原来的１％和３％，但在１ｍｍｏｌ／ＬＥＤＴＡ存在情况下，Ｉ－对ＮＡＤａｓｅ发光的淬灭作用非常显著，Ｉ－浓度为０．１ｍｏｌ／Ｌ和０．２ｍｏｌ／Ｌ时淬灭分别为原来的２５％和４８％，因此Ｃｕ２＋对维持ＮＡＤａｓｅ结构起重要作用。
In this paper, the properties of NADase, purified from Agkistrodon acutus venom, were studied by fluorescence spectroscopy. The fluorescence intensities of NADase is affected greatly by acidity when pH<6, but weakly when pH>6. The fluorescence intensity decreased when Cu2+ was added into the NADase solution. The binding constant (KEM) of Cu2+ to NADase is determined as 5.3×103 (mol/L)-1 at pH7.4 by the fluorescence titration of NADase with Cu2+. The fluorescence intensities of NADase decrease about 1% or 3% when 0.1 mol/L I- or 0.2 mol/L I- is added into the NADase solution respectively. However the fluorescence intensities of NADase are quenched by about 25% or 48% with further addition of 1 mmol/L EDTA into above solutions. Cu2+ can maintained the structure of NADase.
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
1998年第1期53-57,共5页
Chinese Journal of Inorganic Chemistry
基金
中科院长春应化所希土化学与物理开放实验室基金
国家自然科学基金
关键词
蝮蛇毒
糖苷水解酶
NADase
蛇毒
NADase acidity copper(Ⅱ)ion iodine anion fluorescence spectroscopy
