Objective The objectives of this project is to determine the molecular basis for the functional properties of wheat for breadmaking and other food uses, using a combination of biophysical, biochemical and molecular genetic approaches, including the production and analysis of transgenic wheat plants.Spectroscopic studies of whole HMW subunits and subunit peptides have provided a detailed understanding of the structures and properties of the whole subunits and their three structural domains:1. Spectroscopic analyses of purified subunits and repetitive peptides has led to a novel theory for gluten elasticity based on inter-chain hydrogen bonding;2. Comparisons of allelic pairs of HMW subunits associated with good and poor bread making performance have shown differences in their stability to unfolding and specific molecular interactions that may lead to impacts on gluten elasticity;3. A new series of near-isogenic lines which differ in their number and composition of HMW subunits has been produced in the cultivar Pegaso.Transgenic lines have been produced expressing wild type and mutant HMW subunits. Biochemical and functional studies of transgenic lines grown in replicate field trials have demonstrated that the expression of additional HMW subunits can lead to increased elasticity or to more dramatic changes in processing properties, the latter being associated with a high proportion of insoluble glutenin polymers.The underpinning knowledge provided will facilitate the development of new types of wheat with optimised raw material quality using genetic engineering. Wheat flour consists of about 80 % starch, 10 % protein with small amounts of other components such as lipids and pentosans. Although all of these may contribute to the functional properties, the proteins appear to be particularly important in this respect. This is because proteins are the major components of gluten, which forms a network in dough and confers the crucial properties of viscosity (extensibility) and elasticity. A precise balance of these properties is required for different end uses, and this balance in turn depends on the precise composition and properties of the gluten proteins. Gluten consists of over 50 such proteins, which are classically divided into two groups which are present in approximately equal amounts. The glutenins are polymeric and form a highly viscous and elastic network which is plasticised by the monomeric gliadins. Poor processing quality of EU wheats is often related to insufficient elasticity, and the glutenin fraction has therefore been studied in most detail. This has demonstrated the importance of one particular group of proteins, called the High Molecular Weight (HMW) subunits. These proteins will therefore provide answers to three key questions :1. What are the molecular structures of the HMW subunits ?2. How do the structures and interactions of the HMW subunits and other gluten proteins determine the physical (visco-elastic) and functional properties of whole gluten ?3. How do the HMW subunits and other gluten proteins determine the functional properties of doughs ?The results of these studies will allow the amino acid sequences of the individual HMW subunits to be related to their functional properties, via an understanding of their structures and molecular interactions in gluten and doughs. This will allow the use of transformation to improve the quality of wheat for breadmaking and for other food and non-food uses. Fields of science medical and health sciencesmedical biotechnologygenetic engineeringnatural sciencesbiological sciencesbiochemistrybiomoleculesproteinsnatural scienceschemical sciencespolymer sciencesnatural sciencesbiological sciencesbiochemistrybiomoleculeslipidsnatural scienceschemical sciencesorganic chemistryamines Programme(s) FP4-FAIR - Specific research, technological development and demonstration programme in the field of agriculture and fisheries (including agro-industry, food technologies, forestry, aquaculture and rural development), 1994-1998 Topic(s) 3.4.3 - Biotechnology Call for proposal Data not available Funding Scheme CSC - Cost-sharing contracts Coordinator BBSRC Institute of Arable Crops Research EU contribution No data Address Long Ashton Research Station Weston Road BS18 9AF Bristol United Kingdom See on map Total cost No data Participants (9) Sort alphabetically Sort by EU Contribution Expand all Collapse all BBSRC Institute of Food Research United Kingdom EU contribution No data Address Norwich Research Park Colney Lane NR4 7UA Norwich See on map Total cost No data I.N.R.A. - CENTRE DE RECHERCHE DE NANTES France EU contribution No data Address RUE DE LA GERAUDIERE - B.P. 1627 44316 NANTES CEDEX 03 See on map Total cost No data ROTHAMSTED RESEARCH LIMITED United Kingdom EU contribution No data Address Rothamsted Experimental Station AL5 2JQ HARPENDEN See on map Total cost No data SVALØF WEIBULL A.B. Sweden EU contribution No data Address 268 81 SVALÖV See on map Total cost No data UNIVERSIDADE DE AVEIRO Portugal EU contribution No data Address CAMPUS UNIVERSITARIO DE SANTIAGO 3810 AVEIRO See on map Total cost No data UNIVERSITY OF CATANIA Italy EU contribution No data Address Viale A. Doria 6 95125 Catania See on map Total cost No data UNIVERSITY OF GRONINGEN Netherlands EU contribution No data Address NIJENBORGH, 4 9747 AG GRONINGEN See on map Total cost No data UNIVERSITY OF LUND Sweden EU contribution No data Address GETINGEVÄGEN, 60 - P.O. BOX 117 221 00 LUND See on map Total cost No data UNIVERSITÀ DEGLI STUDI DELLA TUSCIA Italy EU contribution No data Address Via S. Camillo de Lellis 01100 VITERBO See on map Total cost No data
