Development of saxitoxin-conjugated affinity gels.
Saxitoxin (STX) and its analogues accumulated in bivalves cause food poisoning through the blockade of sodium channels in the nervous system. In the current studies, STX-conjugated agarose gels as affinity chromatography reagents were prepared for investigation of the fate of the toxins in natural environments and in the human body. A carboxyl moiety was introduced through positions C11 and C13 to leave the most characteristic part of the molecule intact. Two types of synthesized derivatives, 11-(2-carboxyethylthio)saxitoxin and 13-O-hemisuccinyldecarbamoylsaxitoxin, were successfully conjugated to Sepharose 4B in high yield. Affinity gels containing 500 nmol of STX or decarbamoylsaxitoxin per milliliter of gel were accomplished by masking the residual amino groups by acetylation. Finally, the STX-conjugated affinity gel was effective for concentrating STX-binding proteins from pufferfish and bullfrog plasma.
Laboratory of Bioorganic Chemistry, Graduate School of Life Sciences, Tohoku University, Sendai 981-8555, Japan
Ryuichi
R
Watanabe
Ritsumi
R
Samusawa-Saito
Yasukatsu
Y
Oshima
D029845:Amphibian Proteins / Q000302:isolation & purification / Q000378:metabolism; D000818:Animals; D002352:Carrier Proteins / Q000302:isolation & purification / Q000378:metabolism; D002846:Chromatography, Affinity / Q000295:instrumentation / Q000379:methods; D002847:Chromatography, Agarose / Q000295:instrumentation / Q000379:methods; D006801:Humans; D015394:Molecular Structure; D010949:Plasma / Q000737:chemistry; D011485:Protein Binding; D011892:Rana catesbeiana; D012530:Saxitoxin / Q000031:analogs & derivatives / Q000737:chemistry* / Q000378:metabolism; D015222:Sodium Channels / Q000378:metabolism; D023721:Tetraodontiformes
D029845:Amphibian Proteins; D002352:Carrier Proteins; D015222:Sodium Channels; C027525:saxitoxin-binding protein, Rana catesbeiana; D012530:Saxitoxin