Direct and Efficient Production of Ethanol from Cellulosic Material with a Yeast Strain Displaying Cellulolytic Enzymes

• DOI: 10.1128/aem.68.10.5136-5141.2002
• Publication Date: 2002-09-25T18:02:42Z
• Authors: Yasuya Fujita; Shouji Takahashi; Mitsuyoshi Ueda; Atsuo Tanaka; Hirofumi Okada; Yasushi Morikawa; Takashi Kawaguchi; Motoo Arai; Hideki Fukuda; Akihiko Kondo
• Keywords: Ethanol Fermentation

ABSTRACT For direct and efficient ethanol production from cellulosic materials, we constructed a novel cellulose-degrading yeast strain by genetically codisplaying two cellulolytic enzymes on the cell surface of Saccharomyces cerevisiae . By using engineering system based α-agglutinin, endoglucanase II (EGII) filamentous fungus Trichoderma reesei QM9414 was displayed as fusion protein containing an RGSHis6 (Arg-Gly-Ser-His 6 ) peptide tag in N-terminal region. EGII activity detected pellet fraction but not culture supernatant. Localization RGSHis6-EGII-α-agglutinin confirmed immunofluorescence microscopy. The displaying showed significantly elevated hydrolytic toward barley β-glucan, linear polysaccharide composed average 1,200 glucose residues. In further step, β-glucosidase 1 Aspergillus aculeatus No. F-50 were codisplayed surface. resulting cells could grow synthetic medium β-glucan sole carbon source directly ferment 45 g per liter to produce 16.5 within about 50 h. yield terms grams produced gram carbohydrate utilized 0.48 g/g, which corresponds 93.3% theoretical yield. This result indicates that simultaneous saccharification fermentation cellulose are carried out recombinant enzymes.