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Title: Engineering hydroxyproline‐ O ‐glycosylated biopolymers to reconstruct the plant cell wall for improved biomass processability
Abstract

Reconstructing the chemical and structural characteristics of the plant cell wall represents a promising solution to overcoming lignocellulosic biomass recalcitrance to biochemical deconstruction. This study aims to leverage hydroxyproline (Hyp)‐O‐glycosylation, a process unique to plant cell wall glycoproteins, as an innovative technology for de novo design and engineering in planta of Hyp‐O‐glycosylated biopolymers (HypGP) that facilitate plant cell wall reconstruction. HypGP consisting of 18 tandem repeats of “Ser–Hyp–Hyp–Hyp–Hyp” motif or (SP4)18was designed and engineered into tobacco plants as a fusion peptide with either a reporter protein enhanced green fluorescence protein or the catalytic domain of a thermophilic E1 endoglucanase (E1cd) fromAcidothermus cellulolyticus. The engineered (SP4)18module was extensively Hyp‐O‐glycosylated with arabino‐oligosaccharides, which facilitated the deposition of the fused protein/enzyme in the cell wall matrix and improved the accumulation of the protein/enzyme in planta by 1.5–11‐fold. The enzyme activity of the recombinant E1cd was not affected by the fused (SP4)18module, showing an optimal temperature of 80°C and optimal pH between 5 and 8. The plant biomass engineered with the (SP4)18‐tagged protein/enzyme increased the biomass saccharification efficiency by up to 3.5‐fold without having adverse impact on the plant growth.

 
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NSF-PAR ID:
10131804
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Biotechnology and Bioengineering
Volume:
117
Issue:
4
ISSN:
0006-3592
Page Range / eLocation ID:
p. 945-958
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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