Lytic polysaccharide (mono)oxygenases (LPMOs) perform oxidative cleavage of polysaccharides, and are key enzymes in biomass processing and the global carbon cycle. It has been shown that LPMO reactions may be driven by light, using photosynthetic pigments or photocatalysts, but the mechanism behind this highly attractive catalytic route remains unknown. Here, prompted by the discovery that LPMOs catalyze a peroxygenase reaction more efficiently than a monooxygenase reaction, we revisit these light-driven systems, using an LPMO from Streptomyces coelicolor (ScAA10C) as model cellulolytic enzyme. By using coupled enzymatic assays, we show that HO is produced and necessary for efficient light-driven activity of ScAA10C. Importantly, this activity is achieved without addition of reducing agents and proportional to the light intensity. Overall, the results highlight the importance of controlling fluxes of reactive oxygen species in LPMO reactions and demonstrate the feasibility of light-driven, tunable enzymatic peroxygenation to degrade recalcitrant polysaccharides.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7021734PMC
http://dx.doi.org/10.1038/s41467-020-14744-9DOI Listing

Publication Analysis

Top Keywords

lytic polysaccharide
8
lpmo reactions
8
controlled depolymerization
4
depolymerization cellulose
4
light-driven
4
cellulose light-driven
4
light-driven lytic
4
polysaccharide oxygenases
4
oxygenases lytic
4
polysaccharide monooxygenases
4

Similar Publications

The basidiomycete strain LE-BIN1700 (Agaricales, ) is able to grow on agar media supplemented with individual components of lignocellulose such as lignin, cellulose, xylan, xyloglucan, arabinoxylan, starch and pectin, and also to effectively destroy and digest birch, alder and pine sawdust. produces a unique repertoire of proteins for the saccharification of the plant biomass, including predominantly oxidative enzymes such as laccases (family AA1_1 CAZymes), GMC oxidoreductases (family AA3_2 CAZymes), FAD-oligosaccharide oxidase (family AA7 CAZymes) and lytic polysaccharide monooxygenases (family LPMO X325), as well as accompanying acetyl esterases and loosenine-like expansins. Metabolomic analysis revealed that, specifically, monosaccharides and carboxylic acids were the key low molecular metabolites in the culture liquids in the experimental conditions.

View Article and Find Full Text PDF

A periplasmic protein modulates the proteolysis of peptidoglycan hydrolases to maintain cell wall homeostasis in .

Proc Natl Acad Sci U S A

January 2025

Department of Biological Sciences, College of Natural Sciences, Sungkyunkwan University, Suwon 16419, Republic of Korea.

Bacterial cell wall assembly and remodeling require activities of peptidoglycan (PG) hydrolases as well as PG synthases. In particular, the activity of DD-endopeptidases, which cleave the 4-3 peptide crosslinks in PG, is essential for PG expansion in gram-negative bacteria. Maintaining optimal levels of DD-endopeptidases is critical for expanding PG without compromising its integrity.

View Article and Find Full Text PDF

The Cu site in particulate methane monooxygenase may be used to produce hydrogen peroxide.

Dalton Trans

January 2025

Department of Computational Chemistry, Lund University, Chemical Centre, P. O. Box 124, SE-221 00 Lund, Sweden.

Particulate methane monooxygenase (pMMO) is the most efficient of the two groups of enzymes that can hydroxylate methane. The enzyme is membrane bound and therefore hard to study experimentally. For that reason, there is still no consensus regarding the location and nature of the active site.

View Article and Find Full Text PDF

Theoretical study of the formation of HO by lytic polysaccharide monooxygenases: the reaction mechanism depends on the type of reductant.

Chem Sci

January 2025

State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry College of Chemistry and Chemical Engineering, Xiamen University Xiamen 361005 China

Lytic polysaccharide monooxygenases (LPMOs) are a unique group of monocopper enzymes that exhibit remarkable ability to catalyze the oxidative cleavage of recalcitrant carbohydrate substrates, such as cellulose and chitin, by utilizing O or HO as the oxygen source. One of the key challenges in understanding the catalytic mechanism of LPMOs lies in deciphering how they activate dioxygen using diverse reductants. To shed light on this intricate process, we conducted in-depth investigations using quantum mechanical/molecular mechanical (QM/MM) metadynamics simulations, molecular dynamics (MD) simulations, and density functional theory (DFT) calculations.

View Article and Find Full Text PDF

Cellulose-derived biomaterials offer a sustainable and versatile platform for various applications. Enzymatic engineering of these fibers, particularly using lytic polysaccharide monooxygenases (LPMOs), shows promise due to the ability to introduce functional groups onto cellulose surfaces, potentially enabling further functionalization. However, harnessing LPMOs for fiber engineering remains challenging, partly because controlling the enzymatic reaction is difficult and partly because limited information is available about how LPMOs modify the fibers.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!