Laboratory of cereal biochemistry
Laboratory of cereal biochemistry organized in 1973. Founder and the first head Academician T.B. Darkanbaev. Since 1986, the laboratory was headed by the Doctor of biological Sciences, Professor O.V. Fursov, and from 1998 to the present – candidatе of biological sciences A.A. Khakimzhanov.
Head of laboratory – Khakimzhanov Aidar Atymtaevich, he is a specialist in the field of plant biochemistry, grain enzymology (enzymes of carbohydrate metabolism and their inhibitors), the author of over 60 scientific articles and 5 patents. In 2016 was awarded the Certificate of honor the Ministry of Education and Science of the Republic of Kazakhstan.
Directions of research activities:
- Mechanisms regulation and functioning enzymes of the metabolism of main storage substances in cereal grain starch and protein – amylase and protease complexes
- Biochemical properties and functioning of protein inhibitors of cereal grain amylases
- Regulation and functioning enzymes of the defense system in cereal plants – glucanases and chitinases
- Development of biochemical tests for wheat resistance to pre-harvest sprouting and fungal diseases (fusariosis).
Performed research projects (current):
Title: Project IRN: AP05133823: “Study of chitin and β-glucan binding enzymes in pathogenesis and their application in wheat resistance testing to fusarium” (2018-2020).
Scientific project supervisor: A.A. Khakimzhanov
Basic research methods
Spectrophotometry, gradient centrifugation, protein electrophoresis and isoelectrofocusing, liquid column chromatography, ELISA, cell culture.
- Identified features in the regulation of synthesis and secretion of α-amylase isoforms in the embryo and aleurone layer of wheat. For aleurone cells, a strictly hormone-dependent induction of α-amylase is established, whereas in the germinal shield the enzyme synthesis is predominantly regulated by carbohydrates in the form of sugar-metabolite repression. Many results are priority and make a significant contribution to the understanding of the biochemical mechanisms of grain germination.
- The role of the main isoenzyme groups of wheat α-amylase α-AMY 1 and α-AMY 2 in the formation of the Falling number, an important technological indicator of grain quality, was determined. The results are priority and have great significance in both theoretical and applied aspects.
- The protein inhibitor of endogenous α-amylase in wheat was isolated in a homogeneous state and characterized. The specificity of its action in relation to the two main isogroups of α-amylase has been established. New data on the physicochemical properties of the protein inhibitor have been obtained.
- For the first time, data were obtained on the effect of sodium phytate on wheat α-amylase isoenzymes. The selective inhibitory effect of natural chelator on α-amylase “germination” has been established. Along with a protein inhibitor, sodium phytate can be used as an improver for the quality of bread baked from flour with elevated autolytic activity.
- The isoenzyme composition and organ localization of protective enzymes β-1,3-glucanase and chitinase in wheat was studied. The characteristic of their physicochemical properties and features of induction is given.
- A method of immunochemical testing of wheat for resistance to pre-harvest sprouting has been developed. The essence of the method lies in the identification of α-amylase isoenzymes characteristic of germinating grains with the help of highly specific polyclonal antibodies. The sensitivity of the “sandwich” ELISA for the determination of α-amylase α-AMY 1 is 5-0.05 μg of protein per ml. The method was tested in laboratory conditions, 25 varieties and lines of soft spring wheat were tested for an elevated content of α-amylase “germination”, among which genotypes that are relatively stable and unstable to pre-harvest sprouting were identified.
- A new method for the purification of α-amylase/subtilisin inhibitor using wheat α as immobilized α-amylase α-AMY 1 as an affinity ligand has been developed