Molecular manipulation and modification of the genes encoding the G2 and G4 glycinin subunits

ABSTRACT

The genes encoding the glycinin subunits G2 and G4 were molecularly manipulated and modified to test the possibility of increasing the nutritional value of soybean seed proteins. The recombinant DNAs pSP65/G2HG4, pSP65/G4HG2, pSP65/248 Metl, pSP65/248 Met2,3 and pSP65/248 Metl.2,3 were used in in vitro translation to produce (i) chimeric proteins consisting of reciprocally exchanged acidic and basic G2 and G4 domains and (ii) Gy4 point mutants with an increased number of methionine residues. The ability of the recombinant proteins to assemble into proper quaternary structures was investigated using sucrose gradient fractionation. The data produced by this study could provide valuable clues for the potential improvement of genetically modified crops.