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用远紫外ＣＤ谱研究了皖南尖吻蝮蛇蛇毒３个出血毒素ＡａＨⅠ、ＡａＨⅢ和ＡａＨⅣ的溶液构象，ＡａＨⅠ的α螺旋、β折叠、β转角和无规卷曲的含量分别为２５．８％、１２．７％、２６．８％和３４．７％；ＡａＨⅢ的二级结构含量分别为２３．９％、２０．６％、２３．７％和３１．８％；而ＡａＨⅣ分别为１８．２％、３１．０％、１７．２％和３３．６％。当ｐＨ小于４．０或ｐＨ大于１１．０时，３种出血毒素α螺旋减少而β折叠增多，同时３种出血毒素的酪蛋白水解活性显著下降。ＥＤＴＡ抑制酪蛋白水解活性，表明３种出血毒素均是金属蛋白酶。ＥＤＴＡ、Ｃｕ２＋、Ｚｎ２＋、Ｃａ２＋和Ｍｇ２＋能改变３种出血毒素的二级结构，并影响酪蛋白水解活性。
The solution conformations of three hemorrhagic toxins AaHⅠ, AaHⅢ and AaHⅣ in southern Anhui snake venom were studied by far-UV CD spectra. The content of α-helix, β-sheet, β-turn and random coils of AaHⅠwas 25.8%, 12 .7%, 26.8% and 34.7% respectively. The secondary structure contents of AaHⅢ were 23.9%, 20.6%, 23.7% and 31.8% , 31.0%, 17.2% and 33.6% respectively. When the pH was less than 4.0 or the pH was greater than 11.0, the three hemorrhagic toxin alpha helix decreased and beta sheet increased, while the casein hydrolytic activity of the three hemorrhagic toxins was significantly decreased. EDTA inhibited casein proteolytic activity, indicating that all 3 hemolysins are metalloproteases. EDTA, Cu2 +, Zn2 +, Ca2 + and Mg2 + can change the secondary structure of three hemorrhagic toxins and affect casein proteolytic activity.