Reversible changes of canavalin solubility controlled by divalent cation concentration in crude sword bean extract

Canavalin is a vicilin-class (7S) storage protein found in sword bean (Canavalia gladiata). Our previous report indicated that canavalin is precipitated by the addition of 20 mM MgCl2 to crude sword bean extract. Here, we examined the solubility changes induced by the addition of Mg2+ and Ca2+ at various concentrations. Canavalin tended to be insolubilized at relatively low concentrations of MgCl2 (< 20 mM) and solubilized at relatively high...