Abstract
The saprophytic fungus Trichoderma reesei has long been used
as a model to study microbial degradation of lignocellulosic
biomass. The major cellulolytic enzymes of T. reesei are the
cellobiohydrolases CBH1 and CBH2, which constitute more
than 70% of total proteins secreted by the fungus. However,
their physiological functions and effects on enzymatic hydrolysis
of cellulose substrates are not sufficiently elucidated.
Here, the cellobiohydrolase-encoding genes cbh1 and cbh2
were deleted, individually or combinatively, by using an auxotrophic
marker-recycling technique in T. reesei. When cultured
on media with different soluble carbon sources, all three
deletion strains (Δcbh1, Δcbh2, and Δcbh1Δcbh2) exhibited
no dramatic variation in morphological phenotypes, but their
growth rates increased apparently when cultured on soluble
cellulase-inducing carbon sources. In addition, Δcbh1 showed
dramatically reduced growth and Δcbh1Δcbh2 could hardly
grew on microcrystalline cellulose (MCC), whereas all strains
grew equally on sodium carboxymethyl cellulose (CMC-Na),
suggesting that the influence of the CBHs on growth was carbon
source-dependent. Moreover, five representative cellulose
substrates were used to analyse the influence of the absence
of CBHs on saccharification efficiency. CBH1 deficiency
significantly affected the enzymatic hydrolysis rates of various
cellulose substrates, where acid pre-treated corn stover
(PCS) was influenced the least. CBH2 deficiency reduced the
hydrolysis of MCC, PCS, and acid pre-treated and delignified
corncob but improved the hydrolysis ability of filter paper.
These results demonstrate the specific contributions of
CBHs to the hydrolysis of different types of biomass, which
could facilitate the development of tailor-made strains with
highly efficient hydrolysis enzymes for certain biomass types
in the biofuel industry.
Citations
Citations to this article as recorded by

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Enzyme and Microbial Technology.2025; 190: 110706. CrossRef - The Role of Non-Catalytic Region in Determining the Difference in Efficiency Between Two Cellobiohydrolases Revealed Through a Genetic Approach
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Archives of Microbiology.2024;[Epub] CrossRef - Engineering the secretome of Aspergillus niger for cellooligosaccharides production from plant biomass
Fernanda Lopes de Figueiredo, Fabiano Jares Contesini, César Rafael Fanchini Terrasan, Jaqueline Aline Gerhardt, Ana Beatriz Corrêa, Everton Paschoal Antoniel, Natália Sayuri Wassano, Lucas Levassor, Sarita Cândida Rabelo, Telma Teixeira Franco, Uffe Hasb
Microbial Cell Factories.2024;[Epub] CrossRef - Constitutive overexpression of cellobiohydrolase 2 in Trichoderma reesei reveals its ability to initiate cellulose degradation
Yubo Wang, Meibin Ren, Yifan Wang, Lu Wang, Hong Liu, Mei Shi, Yaohua Zhong
Engineering Microbiology.2023; 3(1): 100059. CrossRef - Inducer-free recombinant protein production in Trichoderma reesei: secretory production of endogenous enzymes and heterologous nanobodies using glucose as the sole carbon source
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Microbial Cell Factories.2023;[Epub] CrossRef - The Influence of Trctf1 Gene Knockout by CRISPR–Cas9 on Cellulase Synthesis by Trichoderma reesei with Various Soluble Inducers
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Bioresource Technology.2022; 364: 128027. CrossRef