PURIFICATION, CHARACTERIZATION AND CONFORMATIONAL ANALYSIS OF A HAEMORRHAGIN FROM THE VENOM OF AGKISTRODON ACUTUS

摘要

AaHIV, a medium-sized toxin with a mol. wt of 44,000, a pI of 5.0 and a low cysteine content, was isolated from the venom of Agkistrodon acutus by ion-exchange and gel filtration chromatography. It had haemorrhagic, lethal and caseinolytic activities, the last of which was inhibited by EDTA, Zn(CH2COO)(2) or CuSO4. The circular dichroism spectrum at pH 7.0 showed two negative bands at 210 nm and 219 nm, corresponding to secondary structure contents of 18.2% alpha-helix, 31.0% beta-sheet, 17.2% beta-turn and 33.6% random-coil. The effect of various pH values or the addition of EDTA or Zn(CH3COO)(2) on the circular dichroism spectrum was also investigated. (C) 1997 Elsevier Science Ltd. [References: 15]