Strontium-EDTA chelate

The BS I lectin requires bound calcium for activity.131 Two moles of calcium and 1.25 moles of magnesium per mole of protein were found by atomic absorption spectroscopy. Inactive, metal-free lectin, obtained by exhaustive dialysis, could be reconstituted by addition of calcium, cadmium, or strontium (magnesium restored 80% of the activity). Although bound-calcium was not removed by dialysis against EDTA, inclusion of this chelating agent in the precipitin reaction resulted in complete inhibition. 

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