Abstract:
Phaseolin, the 7S seed storage protein from common beans (Phaseolus vulgaris L.), partially modified in vivo during seed germination and seedling growth was isolated from cotyledons of 6 day germinated seedlings (phaseolininvivo). SDS-PAGE showed that the pattern of fragments of phaseolin-invivo is similar to that of the phaseolin degraded by legumain - phaseolin-LLP. Native electrophoresis showed that phaseolin-invivo consists of four molecular
forms. 2-D electrophoresis showed that the molecular form of phaseolin-invivo that is similar to phaseolin-LLP retains in its qua ternary structure some of the fragments detected by SDS-PAGE. Phaseolin-invivo retains the property to reversibly associate/dissociate with the changes in pH. At pH 4.6 it is present in its dodecameric form while at pH 8.0 inits protomeric form. The implications of the finding that phaseolin-invivo retains the same property of native phaseolin to associate into dodecamers at acidic pHs are discussed.