Following the LPMO Active Site Throughout Productive-Pathway Turnover: Characterization of Chitin-Bound Intermediates

We have prepared samples of the C–H activating Cu metalloenzyme Cbp21, an AA10 LPMO which participates in the depolymerization of chitin. The samples feature protein which is either bound or unbound to chitin in the Cu(II) and Cu(I) oxidation states. Furthermore, we will prepare turnover intermediates under monooxygenase conditions, and isolate these sample via freeze quench methods. The successful collection of Cu K-edge XAS/EXAFS data will provide insight into the perturbation of the Cu site upon substrate binding, as well as mechanistic insight into the LPMO during mono-oxygenase turnover. We intend to utilize a fluorescence detected-XAS configuration with multi-element, high-sensitivity detector and cryostat available at BM23.