Suchergebnisse

The review describes the history of the development of research on carbohydrasеs conducted at the Department of Chemical Enzymology from the mid-1970s to the present. The results concerning the study of the mechanism and kinetics of the processes of enzymatic conversion of cellulose and renewable plant raw materials under the action of a multi-enzyme cellulases complexes; the role of individual components of these complexes - basic (endoglucanases and cellobiohydrolases) and auxiliary enzymes (polysaccharide monooxygenase, β-glucosidase, xylanase) and their synergistic interaction. The features of using reactors of various designs for bioconversion of plant raw materials are described: periodic type, continuous column type, reactor for hydrolysis in a constant electric field, reactor with intensive mixing by ferromagnetic particles in magnetic field. The possibilities of increasing the reactivity of plant raw materials using various pretreatment methods, as well as the influence of the structural and physico-chemical properties of cellulose on the efficiency of its enzymatic conversion are discussed. Data on the creation of highly active strains of microscopic fungi-producers of cellulases and other carbohydrases using methods of induced mutagenesis - Trichoderma (Hypocrea), Penicillium (Talaromyces), Aspergillus, Chrysosporium (Myceliophtora) spp., as well as data on the composition of the enzyme complexes produced by them and the properties of the enzymes forming them are presented. It describes the creation of expression systems based on P. canescens and P. verruculosum and the production of recombinant producer strains with their help, which made it possible to obtain enzyme preparations (EP) that ensure high efficiency of bioconversion processes of plant raw materials, as well as to create producers of a wide range of carbohydrases for practical use in various fields of industry and agriculture. A number of industrially important EP obtained using the P. verruculosum expression system are currently being produced at the Agroferment LLC plant.

New recombinant strains of Penicillium verruculosum have been created with a high level of expression of homologous endo-β-1,4-glucanase II and heterologous phytase A A. niger, as well as heterologous endo-1,4-β-xylanase E P. canescens and phytase A A. niger, allowing to obtain highly active feed enzyme preparations (AF) capable of simultaneously signi cantly reducing viscosity non-starch polysaccharides, as well as increase the bioavailability of phosphorus and minerals of grain-based feed and, thus, increase the digestibility of nutrients of agricultural animal and poultry feed. Speci c AF activities for speci c substrates (xylanau, β-glucan, phytate) were studied, the qualitative and quantitative component composition of new AF was determined. On the basis of a new enzyme preparation containing homologous endo-β-1,4-glucanase II and heterologous phytase A A. niger, a recipient strain ∆nia D - was obtained, into which heterologous endo-1,4-β-xylanase E P. canescens was successfully cloned and, thus, a promising producer of three target enzymes was obtained simultaneously.