Dataset Information

Engineering Pichia pastoris with surface-display minicellulosomes for carboxymethyl cellulose hydrolysis and ethanol production.

ABSTRACT:

Backgrounds

Engineering yeast as a consolidated bioprocessing (CBP) microorganism by surface assembly of cellulosomes has been aggressively utilized for cellulosic ethanol production. However, most of the previous studies focused on Saccharomyces cerevisiae, achieving efficient conversion of phosphoric acid-swollen cellulose (PASC) or microcrystalline cellulose (Avicel) but not carboxymethyl cellulose (CMC) to ethanol, with an average titer below 2 g/L.

Results

Harnessing an ultra-high-affinity IM7/CL7 protein pair, here we describe a method to engineer Pichia pastoris with minicellulosomes by in vitro assembly of three recombinant cellulases including an endoglucanase (EG), an exoglucanase (CBH) and a ?-glucosidase (BGL), as well as a carbohydrate-binding module (CBM) on the cell surface. For the first time, the engineered yeasts enable efficient and direct conversion of CMC to bioethanol, observing an impressive ethanol titer of 5.1 g/L.

Conclusions

The research promotes the application of P. pastoris as a CBP cell factory in cellulosic ethanol production and provides a promising platform for screening the cellulases from different species to construct surface-assembly celluosome.

SUBMITTER: Dong C

PROVIDER: S-EPMC7296672 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Publications

Engineering <i>Pichia pastoris</i> with surface-display minicellulosomes for carboxymethyl cellulose hydrolysis and ethanol production.

Dong Ce C Qiao Jie J Wang Xinping X Sun Wenli W Chen Lixia L Li Shuntang S Wu Ke K Ma Lixin L Liu Yi Y

Biotechnology for biofuels 20200615

<h4>Backgrounds</h4>Engineering yeast as a consolidated bioprocessing (CBP) microorganism by surface assembly of cellulosomes has been aggressively utilized for cellulosic ethanol production. However, most of the previous studies focused on <i>Saccharomyces cerevisiae</i>, achieving efficient conversion of phosphoric acid-swollen cellulose (PASC) or microcrystalline cellulose (Avicel) but not carboxymethyl cellulose (CMC) to ethanol, with an average titer below 2 g/L.<h4>Results</h4>Harnessing a ...[more]

PMID: 32549912

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