Preliminary X-ray diffraction study on haemorrhagin AaHIII from snake venom of Agkistrodon acutus

摘要

Haemorrhagins, which cause local haemorrhage or even death after injection into experimental animals, exist widely in many kinds of snake venoms. Almost all the haemorrhagins reported are zinc-metalloproteinases with highly conserved amino acid sequences. Some of them could degrade the proteins in matrices so that they are the important targets for drugs to combat diseases such as arthritis and cancer. Snake venom metalloproteinases can be divided into three classes based on their molecular weights:low molecular weight (20--30 ku), medial molecular weight (30--60 ku) and high molecular weight (60--90 ku). Two crystal structures of snake venom metalloproteinases, adamalysin II from the eastern diamondback rattlesnake venom and atrolysin C from the western diamondback rattlesnake venom, were solved recently. Both two proteins have similar tertiary structures although they are quite different in haemorrhagic activities.