Enzymatic properties of the Duvernoy's secretion of Blanding's tree snake (Boiga blandingi) and of the mangrove snake (Boiga dendrophila).

Duvernoy's secretion from representatives of the colubrid genus Boiga has been shown by other workers: (1) to contain an alpha-bungarotoxin-like component (Blanding's tree snake, Boiga blandingi); (2) to exhibit acetylcholine receptor binding activity (the brown tree snake, Boiga irregularis); and (3) to react strongly (B. blandingi and the mangrove snake, Boiga dendrophila) with antisera raised against elapid venoms. The present study provides the first evidence for the presence of acetylcholinesterase, a common elapid enzyme, in the Duvernoy's secretion of B. dendrophila and B. blandingi at levels of 122 +/- 7 and 0.36 +/- 0.02 International Enzyme Units, respectively. Constants for inhibition by eserine were 1.25 x 10(-7) M and 2.79 x 10(-7) M, respectively. The Duvernoy's secretion of B. dendrophila exhibited significant phospholipase and haemolytic activities, whereas phosphodiesterase was only weakly present and no thrombin-like activity was observed.