The geographic variations of pitviper venoms are often quantitative,i.e.the proportionaldifferences of certain venom proteins.However,we found recently that the acidic phospholipases A_2(PLAs)of prairie rattlesnake(Crotalus v.vividis)venoms collected in six states in U S.A.showedrather complicate variations.Up to four acidic PLAs which were purified by HPLC from the venomdiffered both qualitatively and quantitatively,following a North-South transition.On the other hand,……
