Development of novel cellulases fused with crystal-disrupting protein

2014 Fiscal Year Final Research Report

• Project/Area Number: 25820396
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Biofunction/Bioprocess
• Research Institution: Hokkaido University (2014); Tohoku University (2013)
• Principal Investigator: NAKASHIMA Kazunori 北海道大学, 工学(系)研究科(研究院), 准教授 (50540358)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: バイオマス分解 / 前処理 / 融合タンパク質

Outline of Final Research Achievements

We constructed novel fusion enzymes consisting of Bacillus subtilis expansin EXLX1 and Clostridium thermocellum endoglucanase CelD. These two components are directly fused, or fused using flexible glycine-serine peptide linkers (GGGGS, GS linker) with different lengths: a triplicate (GGGGS)3 linker (GS3) and a sextuple (GGGGS)6 linker (GS6), resulting in fusion enzymes EXLX1-CelD, EXLX1-GS3-CelD and EXLX1-GS6-CelD. The binding ability and digestibility of these fusion enzymes towards a series of cellulose substrates with different crystallinity index (CrI) was examined. Fused with EXLX1, CelD showed higher binding ability to various kinds of cellulose. In the degradation of cellulose, EXLX1-GS3-CelD exhibited the highest degradation activity among the fusion enzymes examined, suggesting that linker length between the two proteins has a significant impact on the activity of the fusion enzyme. EXLX1-GS3-CelD was found to function more effectively towards higher crystalline celluloses.

Free Research Field

生物反応工学