Iron Incorporation Both Intra- and Extra-Cellularly Improves the Yield and Saccharification of Switchgrass (Panicum virgatum L.) Biomass

Chien-Yuan Lin, Bryon Donohoe, Yannick Bomble, Haibing Yang, Manal Yunes, Nicholas Sarai, Todd Shollenberger, Stephen Decker, Xiaowen Chen, Maureen McCann, Melvin Tucker, Hui Wei, Michael Himmel

Research output: Contribution to journalArticlepeer-review

3 Scopus Citations


Background: Pretreatments are commonly used to facilitate the deconstruction of lignocellulosic biomass to its component sugars and aromatics. Previously, we showed that iron ions can be used as co-catalysts to reduce the severity of dilute acid pretreatment of biomass. Transgenic iron-accumulating Arabidopsis and rice plants exhibited higher iron content in grains, increased biomass yield, and importantly, enhanced sugar release from the biomass. Results: In this study, we used intracellular ferritin (FerIN) alone and in combination with an improved version of cell wall-bound carbohydrate-binding module fused iron-binding peptide (IBPex) specifically targeting switchgrass, a bioenergy crop species. The FerIN switchgrass improved by 15% in height and 65% in yield, whereas the FerIN/IBPex transgenics showed enhancement up to 30% in height and 115% in yield. The FerIN and FerIN/IBPex switchgrass had 27% and 51% higher in planta iron accumulation than the empty vector (EV) control, respectively, under normal growth conditions. Improved pretreatability was observed in FerIN switchgrass (~ 14% more glucose release than the EV), and the FerIN/IBPex plants showed further enhancement in glucose release up to 24%. Conclusions: We conclude that this iron-accumulating strategy can be transferred from model plants and applied to bioenergy crops, such as switchgrass. The intra- and extra-cellular iron incorporation approach improves biomass pretreatability and digestibility, providing upgraded feedstocks for the production of biofuels and bioproducts.

Original languageAmerican English
Article number55
Number of pages15
JournalBiotechnology for Biofuels
Issue number1
StatePublished - 2021

Bibliographical note

Publisher Copyright:
© 2021, The Author(s).

NREL Publication Number

  • NREL/JA-2700-79392


  • Ferritin
  • High-throughput hot-water pretreatment
  • Iron co-catalyst
  • Perls’ Prussian blue staining
  • Saccharification
  • Sugar release
  • Transgenic switchgrass


Dive into the research topics of 'Iron Incorporation Both Intra- and Extra-Cellularly Improves the Yield and Saccharification of Switchgrass (Panicum virgatum L.) Biomass'. Together they form a unique fingerprint.

Cite this