Synthesis of Gluten-Forming Polypeptides. 1. Biosynthesis of Gliadins and Glutenin Subunits

Abstract

Five winter wheat cultivars--GK Othalom (HMW-GS composition 2*, 7+8, 5+10), Ukrainka (1, 7+8, 5+10), Palotás (2*, 7+9, 5+10), Ködmön (2*, 7+8, 5+10), and Csongrád (2*, 7+9, 2+12)--grown in Hungary and harvested in the year 2005 were studied. The biosynthesis of gluten-forming polypeptides was followed starting at the 12th day after anthesis to the 53rd. Fresh kernel weight, moisture, and dry matter content of fresh kernels and gliadin and glutenin contents were determined. Gliadin components, total amounts of HMW and LMW polypeptides, and individual HMW polypeptides were determined using a RP-HPLC technique. Although considerable quantitative differences were observed concerning the content of total protein, gliadin, glutenin, and individual gluten-forming polypeptides, the character of accumulation of protein components--determined on the basis protein mass/kernel--was the same for the all of the cultivars studied and could be presented by a sigmoid curve. Small quantities of the gliadin and glutenin monomers may be detected in early stages of kernel development, but the bulk of these proteins is synthesized in later stages of development. It is generally suggested by specialists that the formation and accumulation of glutenin polymers starts later than the synthesis of monomers. Experimental data presented in this paper confirm this suggestion and show that in the first phase of protein synthesis the monomers are in "free" form; polymeric glutenin is detected only later. HMW glutenin subunits are synthesized synchronously, and quantitatively the polypeptides coded by chromosomes D and B dominate.

The influence of Fusarium infection and growing location on the quantitative protein composition of (part I) emmer (Triticum dicoccum)

“…The explanations given for this include that the changes in glutenin synthesis during the later stages of kernel maturation occur largely due to a reduced protein synthesis invoked by Fusarium infection and the inhibition of protein synthesis by the accumulation of DON [5,8,11]. In contrast, another study found no gliadin and glutenin monomer synthesis at diVerent maturation stages; just polymeric glutenin formation was detected in the later stages [12].…”

“…A change in the synthesis behaviour at diVerent maturation stages has been postulated as an explanation for this observation [11]. Studies focusing on the synthesis of cereal seed storage proteins did not show any alterations in the synthesis stages during grain maturation; only a belated polymerization of glutenins was noted [12]. An inXuence of Fusarium infection on LMW glutenin degradation has been shown in a study which focused on suboptimal storage conditions [13].…”

The influence of Fusarium infection and growing location on the quantitative protein composition of (Part II) naked barley (Hordeum vulgare nudum)

“…A change in the synthesis behaviour at different maturation stages has been postulated as an explanation for this observation [11]. However, a study focusing on the synthesis of cereal seed storage proteins did not show any alterations in the synthesis stages during grain maturation; only a belated polymerization of glutenins was noted [12].…”

Expression and Development of Wheat Proteins during Maturation of Wheat Kernel and the Rheological Properties of Dough Prepared from the Flour of Mature and Immature Wheat

“…Although the grain productivity is a major concern for wheat growers, millers are interested in the functional properties of flour. Thus, there have been many attempts to predict final wheat product quality in the early stages of kernel development (Abonyi et al, 2007;Dupont et al, 2000;Greene et al, 1985;Iametti et al, 2006;Johansson et al, 1994;Ng et al, 1990;Uhlen et al, 2000).…”

“…As described above, several authors have studied compositional changes in gluten proteins during kernel development (Abonyi et al, 2007;Bartels and Thompson, 1986;Greene et al, 1985;Grimwade et al, 1996;Iametti et al, 2006;Johansson et al, 1994;Mecham et al, 1981;Ng et al, 1990;Skerritt et al, 1988). However, relatively few studies have examined individual gluten proteins at the subunit level.…”