Liu ZL, Li HN, Song HT, Xiao WJ, Xia WC, Liu XP, Jiang ZB. Construction of a trifunctional cellulase and expression in Saccharomyces cerevisiae using a fusion protein.
BMC Biotechnol 2018;
18:43. [PMID:
30005661 PMCID:
PMC6044064 DOI:
10.1186/s12896-018-0454-x]
[Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 07/04/2018] [Indexed: 01/11/2023] Open
Abstract
Background
Cellulose is the most important component of lignocellulose, and its degradation requires three different types of enzymes to act synergistically. There have been reports of single gene duality, but no gene has been described to have more than two functions. Cloning and expression of fusion cellulases containing more than two kinds of catalytic domains has not been reported thus far.
Results
We synthesized three different cellulase genes and linked the three catalytic domains with a (G4S)3 flexible linker. The trifunctional cellulase gene (BCE) containing three types of cellulase functions was constructed and expressed in S. cerevisiae successfully. The β-glucosidase, the exoglucanase and the endoglucanase activity of the trifunctional cellulase BCE reached 16.80 IU/mg, 2.26 IU/mg and 20.67 IU/mg, which was 46.27, 6.73 and 46.20% higher than the activities of the β-glucosidase BG, the endoglucanase CBH and the endoglucanase EG. The filter paper enzyme activity of BCE was higher than those of BG, CBH and EG, reached 2.04 IU/mg.
Conclusions
The trifunctional cellulase BCE was designed based on β-glucosidase BG, endoglucanase EG and exoglucanase CBH, and it possessed β-glucosidase activity, endoglucanase activity and exoglucanase activity simultaneously. The BCE has better filter paper activity, it means the potential practical application.
Electronic supplementary material
The online version of this article (10.1186/s12896-018-0454-x) contains supplementary material, which is available to authorized users.
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