High throughput microchip-based separation and quantitation of high-molecular-weight glutenin subunits

Knowledge of glutenin subunit composition is important for the prediction of the genetic potential of breeding lines as these proteins are known to be responsible for the main differences in bread-making quality. In this study, a commercial high throughput microchip capillary electrophoresis-sodium dodecyl sulfate (microchip CE) platform, LabChip 90, was evaluated for qualitative and quantitative analyses of HMW-GS. 130 French common wheat varieties of known composition were analyzed for rapid identification and the allocation of individual HMW-GS. In addition, the HMW-GS were individually quantified and the ratio of HMW-GS to LMW-GS was determined for genotype comparison. The microchip CE analysis provides comparable resolution and sensitivity to conventional RP-HPLC for identification of the HMW-GS but at a time scale of approximately 100 times faster (45 s per sample analysis versus 80 min for RP-HPLC). The results show that the high throughput microchip CE method can be used for routine identification and quantitation of glutenin subunits, in particular for screening wheat quality and wheat cultivar development activities where large numbers of samples are to be evaluated.