Amaranth globulin polypeptide heterogeneity

QUIROGA, A.V.; MARTÍNEZ, N.E.; AÑÓN, M.C.

The Protein Journal

Año: 2007 vol. 26 p. 327 - 333

1572-3887

The polypeptides integrating amaranth globulin-p and 11S-globulin were characterized bytwo-dimensional electrophoresis, ion-exchange chromatography and RP-HPLC. All polypeptidesexhibited charge and hydrophobic heterogeneity. Almost all acid (A, pI 5–7) and basic(B, pI 9–10) polypeptides were present in both globulins, and the same happened with theunprocessed M polypeptides with pI in the range of 7–7.5 which fits well with a sequencecontaining both the A and B polypeptides. There were other polypeptides only present in11S-globulin, like some of 41 and 16 kDa, which might come from another precursor or be theproducts of a different processing of the propolypeptide. These results suggested that,although amaranth subunits from different subfamilies are interchangeable in differentoligomers, some structural differences between them might affect the assembly of globulinmolecules. Structural differences arising from this behavior could account for the differentphysicochemical properties of globulin molecules.