Carbohydrases: 50 Years of Research at the Department of Chemical Enzymology of Moscow State University—History and Prospects

Abstract

This 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 time. The results concerning the research on the mechanism and kinetics of the processes of enzymatic conversion of cellulose and renewable plant raw materials under the action of multienzyme cellulase complexes; and the role of individual components of these complexes—basic (endoglucanases and cellobiohydrolases) and auxiliary enzymes (polysaccharide monooxygenase, β-glucosidase, xylanase)—as well as their synergistic interaction, is described. The features of using reactors of various designs for bioconversion of plant raw materials are also described: periodic type, continuous column type, reactor for hydrolysis in a constant electric field, and 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 physicochemical properties of cellulose on the efficiency of its enzymatic conversion are discussed. The 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, and Chrysosporium (Myceliophtora) spp., as well as the 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 (EPs) that ensure highly efficient bioconversion processes of plant raw materials and create producers of a wide range of carbohydrases for practical use in various fields of industry and agriculture. A number of industrially important EPs obtained using the P. verruculosum expression system are currently being produced at the Agroferment plant.