Electrophoresis of gluten proteins

However, because many of the other proteins and subunits have similar sizes, these bands overlap in the gel. 

Several approaches have been devised to separate the different groups in the complex mixture and to permit individual proteins or subunits to be identified and quantified. A two-step SDS-PAGE procedure was introduced by Singh and Shepherd (1988) in which the imreduced total protein is first loaded on the gel. The gliadins and other monomeric components are allowed to rim ahead of the polymeric components, which form a smear near the origin. The proteins from the smear are then removed and run under reducing conditions on SDS-PAGE. The result of this second step for a 

Procedures for effecting sharper separation of monomeric from polymeric fractions based on solubility have been reported by Fu and Kovacs (1999) and Fu and Sapirstein (1996). The extent of the error has been investigated by Cinco-Moroyoqui (2001), who introduced an alternative procedure for quantifying glutenin subunits. This consisted of fraction collection of the polymeric protein from SE-HPLC followed by reduction 

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