Discovery of a Copper-Binding Carbohydrate-Binding Module Regulating the Activity of Lytic Polysaccharide Monooxygenases.

ABSTRACT: Lytic polysaccharide monooxygenases (LPMOs) are monocopper enzymes that oxidatively cleave recalcitrant polysaccharides such as cellulose. Like other redox enzymes, LPMOs face challenges in handling reactive oxygen species (ROS) generated at their active site, which must be controlled to prevent damaging off-pathway reactions. In the case of copper catalysts, oxidative damage can become self-reinforcing, as released copper from damaged catalytic centers promotes additional ROS formation via abiotic redox cycling. Here we show that a subgroup of carbohydrate-binding modules (CBM2s), exclusively tethered to cellulose-active LPMOs, has evolved the ability to bind copper. The copper site, found on the opposite side of the CBM from the cellulose-binding surface, confers redox protection through

SUBMITTER: Forsberg Z 

PROVIDER: S-EPMC12703677 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature