The characterisation and mapping of a family of LMW-gliadin genes: effects on dough properties and bread volume.
Analysis of a cDNA library from wheat cv Wyuna endosperm, indicated a significant size and sequence variation among seed-endosperm protein genes. In this study, a family of low-molecular-weight seed protein genes are analysed that are related to the gliadins and the low-molecular-weight glutenin subunits. Sequence analysis and comparison of these proteins showed that they are closely related to a 17-kDa protein from barley, epsilon hordein, which plays a role in beer foam stability in the brewing industry. Mapping of these genes in wheat shows that they are located on group 7 and 4 chromosomes, as opposed to a group 1 and 6 location for the glutenins and gliadins. It is possible that this family of proteins forms a new class of seed-endosperm proteins important in defining the quality characteristics of wheat flour. Therefore, a representative gene from this family was expressed in Escherichia coli and the purified protein was supplemented into a base wheat flour. Rheological analysis showed that the protein effected dough strength and resistance break down during mixing of the dough, and provided a 20% increase in loaf height after baking.
Clarke
Bryan C
BC
CSIRO - Plant Industry, PO Box 1600, Canberra, ACT, Australia 2601. bryan.clarke@pi.csiro.au
Phongkham
Tanya
T
Gianibelli
Maria Cristina
MC
Beasley
Helen
H
Bekes
Ferenc
F
D000595:Amino Acid Sequence; D001483:Base Sequence; D001939:Bread; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism; D020224:Expressed Sequence Tags; D017343:Genes, Plant; D005903:Gliadin / Q000235:genetics*; D005983:Glutens / Q000031:analogs & derivatives* / Q000235:genetics*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010940:Plant Proteins / Q000235:genetics; D010957:Plasmids / Q000378:metabolism; D020641:Polymorphism, Single Nucleotide; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D013997:Time Factors; D014908:Triticum / Q000235:genetics*
D018076:DNA, Complementary; D010940:Plant Proteins; D005983:Glutens; D005903:Gliadin; C037302:glutenin