Issue 17, 2023

Enhanced microbial production of protocatechuate from engineered sorghum using an integrated feedstock-to-product conversion technology

Abstract

Building a stronger bioeconomy requires production capabilities that are largely generated through microbial genetic engineering. Plant feedstocks can additionally be genetically engineered to generate desirable feedstock traits and provide precursors for direct microbial conversion into desired products. The oleaginous yeast Rhodosporidium toruloides is a promising organism for this type of conversion as it can grow on a wide range of deconstructed biomass and consume a variety of carbon sources. Here, we leveraged R. toruloides native p-coumaric acid consumption pathway to accumulate protocatechuate (PCA) from 4-hydroxybenzoate (4HBA) released from a sorghum feedstock line genetically engineered to overproduce 4HBA. We did so by generating and evaluating an R. toruloides strain that accumulates PCA, RSΔ12623. We then show that at two scales a cholinium lysinate pretreatment with enzymatic saccharification successfully extracts 95% of the 4HBA from the engineered sorghum biomass while producing deconstructed lignin that can be more efficiently depolymerized in a subsequent thermochemical reaction. We also demonstrate that strain RSΔ12623 can convert more than 95% of 4HBA to PCA while consuming >95% of the glucose and >80% of the xylose present in sorghum hydrolysates. Finally, to evaluate the scalability of such fermentations, we conducted the conversion of 4HBA to PCA in a 2 L bioreactor under controlled conditions. This work demonstrates the potential of purposefully producing aromatic precursors in planta that can be liberated during biomass deconstruction for direct microbial conversion to desirable bioproducts.

Graphical abstract: Enhanced microbial production of protocatechuate from engineered sorghum using an integrated feedstock-to-product conversion technology

Article information

Article type
Paper
Submitted
05 mai 2023
Accepted
28 jul 2023
First published
03 ago 2023

Green Chem., 2023,25, 6797-6808

Author version available

Enhanced microbial production of protocatechuate from engineered sorghum using an integrated feedstock-to-product conversion technology

V. E. Garcia, V. Pidatala, C. A. Barcelos, D. Liu, P. Otoupal, O. Wendt, H. Choudhary, N. Sun, A. Eudes, E. R. Sundstrom, H. V. Scheller, D. H. Putnam, A. Mukhopadhyay, J. M. Gladden, B. A. Simmons and A. Rodriguez, Green Chem., 2023, 25, 6797 DOI: 10.1039/D3GC01481A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements