Abstract

The genes of endoglucanases EG2 (36.2 kDa) Penicillium verruculosum and LAM (30.8 kDa) Myceliophthora thermophila were cloned in P. verruculosum recombinant strain. New enzyme preparations with highly stable activity against beta-glucan and laminarin were obtained and investigated, homogeneous enzymes EG2 (EC 3.2.1.4) and LAM (EC 3.2.1.6) being purified and characterized. For beta-glucan, the EG2 K (m) value was found to be 10 times higher than that for LAM; however, EG2 demonstrated greater processivity due to its higher k (cat). The pH and temperature optima of EG2 and LAM activity against barley beta-glucan overlapped and were 4.3-4.9 and 61-67A degrees C, respectively, and EG2 appeared to be more stable than LAM. Oligosaccharides with degree of polymerization 2-10 were formed by hydrolysis of beta-glucan and laminarin by the studied enzymes. The recombinant enzyme preparations were faster and more effective in decreasing the reduced viscosity of wholegrain barley extract than some commercial enzyme preparations. Thus, the new enzyme preparations seem to be rather perspective as feed additives for degradation of non-starch polysaccharides in grain animal feed.

Keywords

endoglucanase; beta-glucan; beta-glucan endodepolymerases; enzyme preparations; Penicillium verruculosum; Myceliophthora thermophila

Published in

Биохимия / Biochemistry
2015, Volume: 80, number: 4, pages: 473-482

UKÄ Subject classification

Biochemistry and Molecular Biology


Publication identifier

DOI: https://doi.org/10.1134/S0006297915040112

Permanent link to this page (URI)

https://res.slu.se/id/publ/84291