Overexpression of Avenin-Like b Proteins in Bread Wheat (Triticum aestivum L.) Improves Dough Mixing Properties by Their Incorporation into Glutenin Polymers

Abstract

Avenin-like b proteins are a small family of wheat storage proteins, each containing 18 or 19 cysteine residues. The role of these proteins, with high numbers of cysteine residues, in determining the functional properties of wheat flour is unclear. In the present study, two transgenic lines of the bread wheat overexpressing avenin-like b gene were generated to investigate the effects of Avenin-like b proteins on dough mixing properties. Sodium dodecyl sulfate sedimentation (SDSS) test and Mixograph analysis of these lines demonstrated that overexpression of Avenin-like b proteins in both transgenic wheat lines significantly increased SDSS volume and improved dough elasticity, mixing tolerance and resistance to extension. These changes were associated with the increased proportion of polymeric proteins due to the incorporation of overexpressed Avenin-like b proteins into the glutenin polymers. The results of this study were critical to confirm the hypothesis that Avenin-like b proteins could be integrated into glutenin polymers by inter-chain disulphide bonds, which could help understand the mechanism behind strengthening wheat dough strength.

Transcriptional and metabolic alternations rebalance wheat grain storage protein accumulation under variable nitrogen and sulfur supply

“…In module 7 GSH showed strong associations with the expression of genes encoding avenin‐like proteins. GSH is a major reservoir of non‐protein reduced S in grains and can also contribute to protein polymerization and consequently affect baking performance (Rhazi et al ., ,b; Tea et al ., ; Zörb et al ., ), whereas the avenin‐like proteins are rich in Cys residues and are known to affect dough strength and resistance break down during the mixing of the dough (Clarke et al ., ; Ma et al ., ). Therefore, this tight relationship between GSH and avenin‐like transcripts is interesting and deserves further investigation.…”

Protein-transitions in and out of the dough matrix in wheat flour mixing

“…For example, several endogenous wheat enzymes, proteases (Bleukx, Brijs, Torrekens, Van Leuven, & Delcour, 1998), endoxylanases (Cleemput, Hessing, van Oort, Deconynck, & Delcour, 1997;Cleemput, Van Laere, Hessing, Van Leuven, Torrekens, & Delcour, 1997), enzyme inhibitors, protease inhibitors (Stauffer, 1987) and xylanase inhibitors (Debyser, Derdelinckx, & Delcour, 1997) affect bread-making performance. Avenin-like proteins can influence dough rheological properties by sulfhydryl/disulphide crosslinks with gluten proteins (Ma, Li, Li, Liu, Liu, Li, et al, 2013). It is also reported that polymeric storage globulins are associated with low bread-making performance (MacRitchie, 1987).…”

Genomics-Enabled Analysis of Puroindoline b2 Genes Identifies New Alleles in Wheat and Related Triticeae Species

“…For example, HMW-glutenin x-and y-type subunits contain four to six cysteines, while α-gliadin and γ-gliadin have six to eight and eight to eleven cysteines, respectively ( Figure S4). Type a-, b-and c-avenin-like proteins (ALPs) have 14, 18-20, and 10-12 cysteine residues, respectively, and some ALPs have effects on dough quality, likely due to the number of cysteine residues for interaction with wheat storage proteins ( Figure S4) [49][50][51][52]. Here, PINB2 identified in the bread wheat genome of CS shares the same cysteine-rich backbone consisting of 10 residues as PINA, PINB, and GSP ( Figure S4).…”