ABSTRACT
Lipoxygenase (LOG) in protein fractions isolated from the leaves of substituted wheat lines was investigated. Three molecular forms of the enzyme were detected. A water deficiency caused the induction of a membrane-bound form (mLOG) and resulted in a decrease in the activity of "soluble" enzymes (s1LOG) and (s2LOG) in most genotypes. A correlation analysis demonstrated the dependence between the level of enzymatic activity and indices of resistance to drought. A genetic control of the s 1 LOG and s2LOG activity at an optimal water supply level was associated with chromosomes 1A, 1D, 3A, 5A, 5B, and 5D, while under the conditions of the modeled soil drought, it was associated with chromosomes 1B and 1D.
Subject(s)
Lipoxygenase/metabolism , Plant Leaves/enzymology , Triticum/enzymology , Water/metabolism , Adaptation, Biological , Chromosomes, Plant , Droughts , Electrophoresis, Polyacrylamide Gel , Genetic Association Studies , Genotype , Isoenzymes/genetics , Isoenzymes/metabolism , Lipoxygenase/genetics , Phenotype , Plant Leaves/genetics , Plant Leaves/growth & development , Solubility , Triticum/genetics , Triticum/growth & development , Water SupplyABSTRACT
Changes in bread-baking properties of wheat flour caused by soybean lipoxygenase and polyunsaturated fatty acids were studied. A positive effect of soybean flour added during dough kneading in an amount of 2% was demonstrated. A method for dough fermentation increasing the loaf volume and improving organoleptic characteristics and total bread-baking estimate is recommended.
Subject(s)
Bread , Cooking , Glycine max/enzymology , Lipoxygenase/metabolism , Cooking/methods , Enzyme Activation , Fermentation , Flour , Food-Processing Industry , Linoleic Acid/metabolism , Oxygen/metabolism , Glycine max/chemistry , Triticum/chemistryABSTRACT
Analysis of the correlation between endogenous lipoxygenase activity and 15 wheat grain quality parameters in three bread wheat populations has shown that enzyme activity influences the weight of 1000 grains, dough deformation energy, dough tenacity, and mixing properties. The correlations between the enzyme activity and the basic quality parameters are negative at high activity levels. The optimum values of specific lipoxygenase activity at which all quality parameters studied have the maximum values range from 108.5 +/- 1.2 to 126.4 +/- 1.9. It has been found that the ability of lipoxygenase to strengthen gluten is related to the lowering of dough extensibility.
Subject(s)
Flour , Lipoxygenase/chemistry , Seeds/chemistry , Seeds/enzymology , Triticum/chemistry , Triticum/enzymology , Food TechnologyABSTRACT
Activity of two enzymes of thiol-disulfide cell metabolism, lipoxygenase (LOX, EC 1.13.11.12) and disulfide-reductase (TPDO, EC 1.8.4.2) was studied in recombinant inbred lines of common wheat ITMI. Their activity in the caryopsis may be connected with the gluten quality, one of the most important traits significant for selection. The activity of lipoxygenase under favorable and droughty environmental conditions was shown to be associated with the quantitative trait locus (QTL) located on chromosome 4BS near the structural gene of a subunit of this enzyme. However, no QTL common to this enzyme and any characteristic of gluten quality have been found. Four loci responsible for the activity of disulfide reductase were identified on chromosomes 4A, 5D, 6A, and7D. Previously, indicators of grain and flour properties, such as elasticity, flour vigor, and grain hardiness were mapped at the same loci. This indicates that the given enzyme participates in the formation of the protein complex upon maturation of wheatgrain. The detected QTL can be involved in further genetic studies designed to establish the regularities of gluten formation.
Subject(s)
Lipoxygenase/genetics , Plant Proteins/genetics , Quantitative Trait Loci , Triticum/genetics , Chromosome Mapping , Lipoxygenase/metabolism , Plant Proteins/metabolism , Seeds/enzymology , Seeds/genetics , Triticum/enzymologyABSTRACT
The effects of intercultivar substitution of individual chromosome pairs (except for 1B, 6D, and 7A) in the wheat cultivars Saratovskaya 29 and Janetzkis Probat, differing in quality, on specific lipoxygenase activity, the grain yield per spike, and the main technological properties of flour and dough were studied. It was demonstrated that the substitution of individual chromosomes of the recipient cultivar Saratovskaya 29 with the homologous chromosomes of the donor cultivar Janetzkis Probat caused significant changes in lipoxygenase activity and several other quality characteristics. The correlations between the lipoxygenase activity and the parameters of physical dough properties were determined. Three molecular forms of lipoxygenase (Lpx-1, Lpx-2, and Lpx-3), differing in the value of surface charge and enzymatic activity, were detected by native PAGE.
Subject(s)
Chromosomes, Plant/genetics , Flour , Lipoxygenase/metabolism , Plant Proteins/genetics , Triticum/genetics , Crosses, Genetic , Enzyme Activation , Isoenzymes/genetics , Isoenzymes/metabolism , Lipoxygenase/genetics , Plant Proteins/metabolism , Triticum/enzymologyABSTRACT
The effects of pH, ionic strength, and medium composition on formation of macrocomplexes of seed storage proteins from wheat, rye, and barley have been studied. It has been found that various noncovalent interactions (electrostatic and hydrophobic interactions and hydrogen bonds) are involved in protein aggregation. Their combined action depends significantly on the biochemical nature of storage proteins and on the medium.