
TY  - JOUR
A1  - Sivri, D. 
A1  - Batey, I. L. 
A1  - Skylas, D. J. 
A1  - Daqiq, L. 
A1  - Wrigley, C. W. 
T1  - Changes in the composition and size distribution of endosperm proteins from bug-damaged wheats
JF  - Australian Journal of Agricultural Research
JO  - Aust. J.  Agric. Res.
Y1  - 2004
VL  - 55
IS  - 4
SP  - 477
EP  - 483
KW  - bug protease, gluten depolymerisation.
UR  - https://doi.org/10.1071/AR03185 
N2  - In this study, grain that had been damaged by the bug Eurygaster spp. and/or Aelia spp., plus some undamaged grain, was selected from hard red winter (HRW) wheat. The changes in endosperm proteins were determined by 2-dimensional (2-D) electrophoresis and size-exclusion high-performance liquid chromatography (SE-HPLC). Although some new protein spots and a slight decrease in the staining intensities of some polypeptides were observed in the 2-D map of the bug-damaged sample, other parts of the gels were similar to the sound (control) sample in terms of relative mobilities and intensities of the polypeptide spots. The major difference between bug-damaged and control samples was that a group of polypeptides, presumably HMW-glutenins, shifted to a more basic region of the map. The SE-HPLC patterns of the total proteins extracted from control and bug-damaged samples in SDS-buffer showed that they differed in the size distribution of the polymeric glutenin protein and in their glutenin/gliadin ratios. The solubility of proteins in SDS buffer was greater in the bug-damaged sample. The &#39;unextractable&#39; polymeric protein (only extractable in SDS-buffer after sonication) (UPP %) was significantly lower in the bug-damaged sample than in the control. The results of 2-D analysis and the decline in the quantity of unextractable proteins in SDS buffer suggest that bug-protease causes dough weakening by degradation of polymeric glutenin, presumably by hydrolysis, and possibly other mechanisms that affect the aggregation of the gluten molecules. 
ER  -

