Isolation, purification and partial characterization of a haemolytic protein from Bidder's organ of toad Bufo melanostictus (Schneider).
A haemolytic protein toxin (BO-HT) from Bidder's organ of toad, B. melanostictus, purified by DEAE-cellulose column chromatography was electrophoretically homogeneous and was glycoprotein in nature (PAS-positive). The molecular weight was estimated to be 14.4 kDa by SDS-polyacrylamide gel electrophoresis. The sensitivity of the haemolysin of different RBC ghost cell preparation was in the order: buffalo > goat > ox > guinea pig > mice > human > chick > rabbit > rat. The haemolytic activity was increased with the decrease in RBC concentration and was produced over a wide range of temperature. Maximum haemolytic effect was produced at 2 hr of incubation. The toxin showed maximum activity at 3 and minimum at 10 pH. Divalent cations (Ca2+, Zn2+, Cu2+, Mg2+) showed inhibitory effect on BO-HT induced haemolysis, whereas sucrose, EDTA, cholesterol, 2-mercaptoethanol and oxygen did not alter the haemolytic activity. Haemolytic activity was reduced by proteolytic enzymes (trypsin, protease) and was totally antagonized by the toad serum.
Gomes
A
A
Department of Physiology, University of Calcutta, India.
Alam
M I
MI
Auddy
B
B
Dasgupta
S C
SC
D000818:Animals; D002025:Bufonidae / Q000378:metabolism*; D004702:Endocrine Glands / Q000737:chemistry*; D006460:Hemolysin Proteins / Q000302:isolation & purification*; D008297:Male; D011506:Proteins / Q000302:isolation & purification*
D006460:Hemolysin Proteins; D011506:Proteins