Subunit structure of soybean 11S globulin.

Abstract

The acidic and the basic subunits were shown to be present in equimolar amounts in the 11S globulin molecule by the densitometric scanning of the SDS gel and the molecular weight consideration.The four acidic subunits (A1, A2, A3 and A4) were found to be present in the approximate molar ratio of 1:1:2:2. Four basic subunits separated and designated as Bl, B2, B3 and B4 based on the relative mobilities in the acidic gel in 7M urea were found to be present in the approximate molar ratio of 1:1:2:2.The four basic subunits were fractionated in approximately same amounts into three different peaks, peak I (B1 and B2), peak II (B3) and peak III (B4) by CM-Sephadex C-50 column chromatography in the presence of 6M urea. Three kinds of intermediary subunits of 11S globulin were fractionated with DEAE-Sephadex A-50 in the absence of reducing agents in 6M urea, and disulfide bonds appeared to participate in the binding between the acidic and the basic subunits in the molar ratio of 1:1 with the following combinations; A1 and A2 combined with B3, A3 with Bi and B2, and A4 with B4. In view of the above results and molecular weight consideration, a new model of subunit structure was proposed for 11S globulin. Catsimpoolaset al

Modification of plant proteins by immobilized proteases

“…Badley et al, 51 Kitamura et al 53 and Iyengar and Ravestein 56 showed that each acidic and basic subunit was linked by one or more disulfide bond(s) forming intermediary subunits. In the absence of 2-mercaptoethanol, Mori et al" 2 indicated the intermediate subunits when the glycinins were analyzed by sodium dodecyl sulfate electrophoresis.…”

A Study on Subunit Groups of Soybean Protein Extracts under SDS‐PAGE

“…Using the similar SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) technique, Hill and Breidenbach [4] found six bands in 7S and seven bands in 11S of soybean cultivar Portage, respectively. Kitamura and his colleagues [5,6] determined four acidic subunits and three or four basic subunits in S. Liu Á J. Gai (&) National Center for Soybean Improvement, National Key Laboratory for Crop Genetics and Germplasm Enhancement, Soybean Research Institute of Nanjing Agricultural University, Nanjing, Jiangsu 210095, People's Republic of China e-mail: sri@njau.edu.cn soybean cultivar Raiden using Disc-PAGE.…”

Evidence for accumulation of the β-subunit of β-conglycinin in soybean [Glycine max (L) Merr.] embryonic axes

“…Globulins are separated into 11S and 7S classes based on their sedimentation rates in sucrose gradients (Hill and Breidenbach 1974). The 11S protein, glycinin, consists of at least four acidic and four basic subunits and is derived by proteolytic cleavage of a precursor polypeptide (Kitamura et al 1976). The 7S protein, β-conglycinin, is a trimer composed of α′-, α-and β-subunits that differentially accumulate during seed development.…”