Effect of highly branched hyphal morphology on the enhanced production of cellulase in Trichoderma reesei DES-15.
The morphology of Trichoderma reesei is a vitally important factor for cellulase productivity. This study investigated the effect of hyphal morphology on cellulase production in the hyper-cellulolytic mutant, T. reesei DES-15. With a distinct morphology, T. reesei DES-15 was obtained through Diethyl sulfite (DES) mutagenesis. The hyphal morphology of DES-15 batch-cultured in a 5-L fermentor was significantly shorter and more branched than the parental strain RUT C30. The cellulase production of DES-15 during batch fermentation was 66 % greater than that of RUT C30 when cultured the same conditions. DES-15 secreted nearly 50 % more protein than RUT C30. The gene expression level of a set of genes (cla4, spa2, ras2, ras1, rhoA, cdc42, and racA) known to be involved in hyphae growth and hyphal branching was measured by quantitative real-time PCR. The transcriptional analysis of these genes demonstrated that a decrease in gene expressions might contribute to the increased hyphal branching seen in DES-15. These results indicated that the highly branching hyphae in DES-15 resulted in increased cellulase production, suggesting that DES-15 may be a good candidate for use in the large-scale production of cellulase.
Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China.|Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China.|Tianjin Key Lab of Industrial Microbiology, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China.
Ronglin
R
He
Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China.
Chen
C
Li
College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China.
Lijuan
L
Ma
Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China. zhang_dy@tib.cas.cn.
Dongyuan
D
Zhang
Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China.
Shulin
S
Chen
Branching; Cellulase production; Hyphal morphology; Submerged cultures; Trichoderma reesei