Self-surface assembly of cellulosomes with two miniscaffoldins on Saccharomyces cerevisiae for cellulosic 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 β-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.

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Automated Yeast Mating Protocol Using Open Reading Frames from Saccharomyces cerevisiae Genome to Improve Yeast Strains for Cellulosic Ethanol Production

JALA Journal of the Association for Laboratory Automation ◽

10.1016/j.jala.2008.12.009 ◽

2009 ◽

Vol 14 (4) ◽

pp. 190-199 ◽

Cited By ~ 16

Author(s):

Stephen R. Hughes ◽

Ronald E. Hector ◽

Joseph O. Rich ◽

Nasib Qureshi ◽

Kenneth M. Bischoff ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Ethanol Production ◽

Cellulosic Ethanol ◽

Open Reading Frames ◽

Yeast Strains ◽

Yeast Mating ◽

Reading Frames

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Efficient ethanol production from beetle-killed lodgepole pine using SPORL technology and Saccharomyces cerevisiae without detoxification

TAPPI Journal ◽

10.32964/tj10.5.9 ◽

2011 ◽

Vol 10 (5) ◽

pp. 9-18 ◽

Cited By ~ 16

Author(s):

J.Y. ZHU ◽

XIAOLIN LUO ◽

SHEN TIAN ◽

ROLLAND GLEISNER ◽

JOSÉ NEGRÓN ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Ethanol Production ◽

Cellulosic Ethanol ◽

Mountain Pine Beetle ◽

Ethanol Yield ◽

Lodgepole Pine ◽

Energy Output ◽

Pine Beetle ◽

Ethanol Yields ◽

Live Tree

This study applied Sulfite Pretreatment to Overcome Recalcitrance of Lignocelluloses (SPORL) to evaluate the potential of mountain pine beetle-killed lodgepole pine for ethanol production using conventional Saccharomyces cerevisiae without hydrolysate detoxification. The results indicate that the beetle-killed trees are more susceptible to SPORL pretreatment than live trees in addition to having enriched glucan and mannan content as reported in the literature. Ethanol yields of 200 and 250 L/metric ton wood were achieved from a live tree and a dead tree (four years after infestation) without process optimization. Ethanol yield of 220 L/metric ton of wood was obtained from a downed tree with more advanced decomposition, which is approximately 10% more than that from a corresponding live tree. Process mass and energy balance analyses suggest that net ethanol energy output (before distillation, lignin energy excluded) from the decomposing tree was approximately 3.2 GJ/metric ton wood, which is 23% more than that from a corresponding live tree. The study demonstrated the robustness of the SPORL process and the utility of beetle-killed trees for cellulosic ethanol production even after many years post mortality.

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