On the formation and role of reactive oxygen species in light-driven LPMO oxidation of phosphoric acid swollen cellulose

TY - JOUR

T1 - On the formation and role of reactive oxygen species in light-driven LPMO oxidation of phosphoric acid swollen cellulose

AU - Möllers, Benedikt

AU - Mikkelsen, Hasse

AU - Simonsen, T.I.

AU - Cannella, David

AU - Johansen, K. S.

AU - Bjerrum, Morten Jannik

AU - Felby, Claus

PY - 2017

Y1 - 2017

N2 - Light-driven activation of lytic polysaccharide monooxygenases (LPMOs) has been attributed to the transfer of high redox potential electrons from excited photopigments to the enzyme. However, due to the formation of reactive oxygen species (ROS) in such a system, not only electrons from the pigments but also ROS could be part of the enzyme mechanism. This work investigates the role of ROS in the oxidation of phosphoric acid swollen cellulose (PASC) by a light-driven LPMO system. Our results clearly show that the addition of superoxide dismutase or catalase to remove ROS did not attenuate the capacity of the light-driven LPMO system to oxidize PASC, as measured by formation of oxidized oligosaccharides. We conclude that ROS are not part of the light-driven LPMO activation; hence, transfer of high redox potential electrons from the excited photopigment to the LPMO remains the most likely mechanism under the conditions tested in this study.

AB - Light-driven activation of lytic polysaccharide monooxygenases (LPMOs) has been attributed to the transfer of high redox potential electrons from excited photopigments to the enzyme. However, due to the formation of reactive oxygen species (ROS) in such a system, not only electrons from the pigments but also ROS could be part of the enzyme mechanism. This work investigates the role of ROS in the oxidation of phosphoric acid swollen cellulose (PASC) by a light-driven LPMO system. Our results clearly show that the addition of superoxide dismutase or catalase to remove ROS did not attenuate the capacity of the light-driven LPMO system to oxidize PASC, as measured by formation of oxidized oligosaccharides. We conclude that ROS are not part of the light-driven LPMO activation; hence, transfer of high redox potential electrons from the excited photopigment to the LPMO remains the most likely mechanism under the conditions tested in this study.

U2 - 10.1016/j.carres.2017.03.013

DO - 10.1016/j.carres.2017.03.013

M3 - Journal article

C2 - 28335986

SN - 0008-6215

VL - 448

SP - 182

EP - 186

JO - Carbohydrate Research

JF - Carbohydrate Research

ER -