SDS-insoluble glutenin polymer formation in developing grains of hexaploid wheat: the role of the ratio of high to low molecular weight glutenin subunits and drying rate during ripening

Abstract

The accumulation of polymeric proteins and the changes in molecular size distribution of these proteins were followed during grain filling and/or premature desiccation. The accumulation behavior of polymeric proteins and their constituent polypeptides (high and low molecular weight glutenin subunits, HMW-GS and LMW-GS) was determined by reversed phase-high performance liquid chromatography using a NaI/propanol purification procedure. With this new extraction and separation procedure, we have demonstrated that there was a coordinated initiation of storage protein biosynthesis, even if the accumulation rate varied greatly between the two main classes of proteins (i.e. monomeric and polymeric fractions). Moreover, the glutenin subunit composition was largely modified during glutenin accumulation. Both the HMW-GS/LMW-GS and HMW-GS-x/HMW-GS-y ratios increased significantly during the whole cell enlargement phase (from 16 to 37 d after anthesis). By applying premature grain desiccation during this physiological phase, we demonstrated that the polymerization index (SDS-insoluble polymers/total polymers) of the glutenin polymers was closely related to the HMW-GS/LMW-GS ratio of these proteins. An increase in the relative proportion of HMW-GS in glutenins caused the proportion of SDS-insoluble polymers to rise during grain desiccation. From these studies, it appears that the modification of the desiccation rate (grain desiccation at a constant temperature with variable relative humidity levels) induced a parallel modification of the glutenin insolubilization rate but did not affect the polymerization index of the glutenins at maturity.

Amaranth, quinoa and oat doughs: Mechanical and rheological behaviour, polymeric protein size distribution and extractability

“…In contrast, the profile of unextractable semolina dough proteins showed a much greater proportion of protein in the first peak (Fig. 7b), in accordance with Gupta et al (1993), Carceller and Aussenac (2001). The SE-HPLC elution profile for extractable proteins in amaranth dough showed few peaks, the greatest proportion being proteins of intermediate size, in both the extractable and unextractable preparations (Fig.…”

“…6a), in decreasing molecular weight order, by: large polymeric proteins (with MW ranging from about 3980 to 2500 kDa), small polymeric proteins (with MW ranging from 300 to 200 kDa), large monomeric proteins (with MW of about 50 kDa) and small monomeric proteins (with MW ranging from about 60 to 20 kDa). These proteins, described by Carceller and Aussenac (2001) and Larroque et al (1996), are represented by high molecular weight (HMW) and low molecular weight (LMW) glutenin proteins (large and small polymeric proteins), gliadins (large monomeric proteins) and albumins and globulins (small monomeric proteins). The amaranth dough profile, in Fig.…”

Study on the interactions between soy and semolina proteins during pasta making

“…1b) show a profile described by Lamacchia et al (2007) and by Lamacchia, Baiano, Lamparelli, La Notte, and Di Luccia (2010), with a polymeric protein peak of glutenin at the extreme left of the profile (Large Polymeric Proteins, LPP > 100,000 Da), followed by a large peak of monomeric gliadin (Large Monomeric Proteins, LMP < 100,000 Da) and finally small peaks of albumins and globulins, known as Small Monomeric Proteins (SMP) (Carceller & Aussenac, 2001;Larroque, Gianibelli, Batey, & MacRitchie, 1996;Larroque, Gianibelli, Batey, & MacRitchie, 1997;Tosi et al, 2005).…”

Improving grain quality: ecophysiological and modeling tools to develop management and breeding strategies

“…Weaker dough from grains that experience one or several days of very high temperature have been related to a marked decrease in the proportion of large molecular size glutenin polymers (ciaffi et al, 1996;corbellini et al, 1998;Wardlaw et al, 2002;don et al, 2005). The aggregation of glutenin proteins, which occurs mainly during grain desiccation after physiological maturity (carceller and aussenac, 2001;Ferreira et al, 2012), is likely the major process responsible for heat-shock-related dough weakening. extended periods of high temperature are common in many cereal-growing areas of the world, and above-optimal temperature is one of the major factors affecting small grain cereal yield and composition (randall and Moss, 1990;Borghi et al, 1995;Graybosch et al, 1995).…”