Cellulases of basidiomycetes for the development of cellulose bioconversion technologies

Abstract

Basidiomycetes cultures were screened for the ability to actively express the cellulases complex. Nutrient media with various forms of sugars were used. From 22 cultures of macromycetes (14 species), a group of six cultures with high level activities of extracellular (Il-11 I. lacteus – 70 IU, Fvv F. velutipes – 78 IU, Pe-1 P. eryngii – 87 IU, Ps-1 L. sulphureus – 83 IU, Mg M. giganteus – 74 IU) and intracellular (Sc-51 S. commune – 102 IU) cellulase complex was selected. Cultures of the species exhibit notable differences in the expression of enzymes, which indicates a significant influence of genetic factors on the process of producer selection. Endo-1,4-β-D-glucanases isozymes for most fungi had a molecular weight of 55 kDa and above, except for S. commune, which had more variability of conformation and weight 12–55 kDa. The culture of Il-11 I. lacteus on media with Avicel and filter paper had the highest activity, its endo- and exo-1,4-β-D-glucanases activities ranged 37–39 IU/mL and 18–20 IU/ mL, respectively. The culture of S. commune Sc-51 is able to accumulate a significant amount of intracellular cellulases, but the production of culture fluid with high viscosity complicates technological manipulations and increases processing time. The obtained data allowed us to isolate an Il-11 I. lacteus culture with stable expression and high activity of the cellulases complex at different carbon sources.

Keywords

• basidiomycota
• cellulases
• endo-1
• 4-β-d-glucanase
• exo-1
• expression