TY - JOUR
T1 - A high performance Trichoderma reesei strain that reveals the importance of xylanase III in cellulosic biomass conversion
AU - Nakazawa, Hikaru
AU - Kawai, Tetsushi
AU - Ida, Noriko
AU - Shida, Yosuke
AU - Shioya, Kouki
AU - Kobayashi, Yoshinori
AU - Okada, Hirofumi
AU - Tani, Shuji
AU - Sumitani, Jun ichi
AU - Kawaguchi, Takashi
AU - Morikawa, Yasushi
AU - Ogasawara, Wataru
N1 - Funding Information:
This work was supported by a grant from the New Energy and Industrial Technology Development Organization (NEDO) Project (P07015).
Publisher Copyright:
© 2015 Elsevier Inc.
PY - 2016/1/1
Y1 - 2016/1/1
N2 - The ability of the Trichoderma reesei X3AB1strain enzyme preparations to convert cellulosic biomass into fermentable sugars is enhanced by the replacement of xyn3 by Aspergillus aculeatus β-glucosidase 1 gene (aabg1), as shown in our previous study. However, subsequent experiments using T. reesei extracts supplemented with the glycoside hydrolase (GH) family 10 xylanase III (XYN III) and GH Family 11 XYN II showed increased conversion of alkaline treated cellulosic biomass, which is rich in xylan, underscoring the importance of XYN III. To attain optimal saccharifying potential in T. reesei, we constructed two new strains, C1AB1 and E1AB1, in which aabg1 was expressed heterologously by means of the cbh1 or egl1 promoters, respectively, so that the endogenous XYN III synthesis remained intact. Due to the presence of wild-type xyn3 in T. reesei E1AB1, enzymes prepared from this strain were 20-30% more effective in the saccharification of alkaline-pretreated rice straw than enzyme extracts from X3AB1, and also outperformed recent commercial cellulase preparations. Our results demonstrate the importance of XYN III in the conversion of alkaline-pretreated cellulosic biomass by T. reesei.
AB - The ability of the Trichoderma reesei X3AB1strain enzyme preparations to convert cellulosic biomass into fermentable sugars is enhanced by the replacement of xyn3 by Aspergillus aculeatus β-glucosidase 1 gene (aabg1), as shown in our previous study. However, subsequent experiments using T. reesei extracts supplemented with the glycoside hydrolase (GH) family 10 xylanase III (XYN III) and GH Family 11 XYN II showed increased conversion of alkaline treated cellulosic biomass, which is rich in xylan, underscoring the importance of XYN III. To attain optimal saccharifying potential in T. reesei, we constructed two new strains, C1AB1 and E1AB1, in which aabg1 was expressed heterologously by means of the cbh1 or egl1 promoters, respectively, so that the endogenous XYN III synthesis remained intact. Due to the presence of wild-type xyn3 in T. reesei E1AB1, enzymes prepared from this strain were 20-30% more effective in the saccharification of alkaline-pretreated rice straw than enzyme extracts from X3AB1, and also outperformed recent commercial cellulase preparations. Our results demonstrate the importance of XYN III in the conversion of alkaline-pretreated cellulosic biomass by T. reesei.
KW - Biomass
KW - Cellulase
KW - GHF 10 xylanase
KW - Trichoderma
KW - β-Glucosidase
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U2 - 10.1016/j.enzmictec.2015.08.019
DO - 10.1016/j.enzmictec.2015.08.019
M3 - Article
C2 - 26672453
AN - SCOPUS:84947968436
SN - 0141-0229
VL - 82
SP - 89
EP - 95
JO - Enzyme and Microbial Technology
JF - Enzyme and Microbial Technology
ER -