Insights from semi-oriented EPR spectroscopy studies into the interaction of lytic polysaccharide monooxygenases with cellulose

Ciano, Luisa; Paradisi, Alessandro; Hemsworth, Glyn R.; Tovborg, Morten; Davies, Gideon J.; Walton, Paul H.

Abstract

Probing the detailed interaction between lytic polysaccharide monooxygenases (LPMOs) and their polysaccharide substrates is key to revealing further insights into the mechanism of action of this class of enzymes on recalcitrant biomass. This investigation is somewhat hindered, however, by the insoluble nature of the substrates, which precludes the use of most optical spectroscopic techniques. Herein, we report a new semi-oriented EPR method which evaluates directly the binding of cellulose-active LPMOs to crystalline cellulose. We make use of the intrinsic order of cellulose fibres in Apium graveolens (celery) to orient the LPMO with respect to the magnetic field of an EPR spectrometer. The subsequent angledependent changes observed in the EPR spectra can then be related to the orientation of the g matrix principal directions with respect to the magnetic field of the spectrometer and, hence, to the binding of the enzyme onto the cellulose fibres. This method, which does not require specific modification of standard CW-EPR equipment, can be used as a general procedure to investigate LPMO–cellulose interactions.

Citation

Ciano, L., Paradisi, A., Hemsworth, G. R., Tovborg, M., Davies, G. J., & Walton, P. H. (2020). Insights from semi-oriented EPR spectroscopy studies into the interaction of lytic polysaccharide monooxygenases with cellulose. Dalton Transactions, 49(11), 3413-3422. https://doi.org/10.1039/c9dt04065j

• Journal Article Type: Article
• Acceptance Date: Mar 5, 2020
• Online Publication Date: Mar 3, 2020
• Publication Date: Mar 21, 2020
• Deposit Date: Mar 5, 2020
• Publicly Available Date: Mar 12, 2020
• Journal: Dalton Transactions
• Print ISSN: 1477-9226
• Electronic ISSN: 1477-9234
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 49
• Issue: 11
• Pages: 3413-3422
• DOI: https://doi.org/10.1039/c9dt04065j
• Public URL: https://nottingham-repository.worktribe.com/output/4093983
• Publisher URL: https://pubs.rsc.org/en/content/articlelanding/2020/DT/C9DT04065J#!divAbstract
• Additional Information: : This document is Similarity Check deposited; : Supplementary Information; : Luisa Ciano (ORCID); : Alessandro Paradisi (ORCID); : Glyn R. Hemsworth (ORCID); : Morten Tovborg (ORCID); : Gideon J. Davies (ORCID); : Gideon J. Davies (ResearcherID); : Paul H. Walton (ORCID); : Single-blind; : Received 17 October 2019; Accepted 5 February 2020; Accepted Manuscript published 3 March 2020; Advance Article published 3 March 2020