1.14.99.53 - 736451 1.14.99.53 1.1 A resolution room-temperature X-ray structure and 2.1 A resolution neutron structure, show a putative dioxygen species equatorially bound to the active site copper with elongated density for the dioxygen, most consistent with a Cu(II)-bound peroxide 740090 1.14.99.53 1.1 A resolution, room-temperature X-ray structure and a 2.1 A resolution neutron structure show a putative dioxygen species equatorially bound to the active site copper. Both structures show an elongated density for the dioxygen, consistent with a Cu(II)-bound peroxide. The coordination environment is consistent with Cu(II). The N-terminal amino group, involved in copper coordination, is present as a mixed neutral and deprotonated form 744364 1.14.99.53 1.55 A resolution structure of N-terminal LPMO10A module reveals deletions of interacting loops that protrude from the core beta-sandwich scaffold in larger LPMO10s 740455 1.14.99.53 analysis of the copper active site 740345 1.14.99.53 calculation of solution structure. Ca2+, Mg2+, Fe3+, Co2+, Zn2+, or Cu2+ ions show binding to an interaction site located between His28 and His114 741326 1.14.99.53 comparative analysis of sequences, solved structures, and homology models from AA9 and AA10 LPMO families.The two LPMO families are highly conserved, structurally they have minimal sequence similarity outside the active site residues 740205 1.14.99.53 crystal structure in the Cu(II)-bound form and photoreduction of the crystalline protein in the x-ray beam, leading to conversion from the initial Cu(II)-oxidized form with two coordinated water molecules, which adopts a trigonal bipyramidal geometry, to a reduced Cu(I) form in a T-shaped geometry with no coordinated water molecules 736451 1.14.99.53 crystallization at pH 3.5. Structure shows shows significant disorder of the active site in the absence of substrate ligand 744629 1.14.99.53 in presence of Zn2+, to 1.55 A resolution, and in presence of Cu2+, to 1.4 AS resolution 741038 1.14.99.53 molecular dynamics interactions between the LPMO and three different surface topologies of crystalline chitin. Most enzyme-substrate interactions involve the polysaccharide chain that is to be cleaved. Enzyme displays a constrained active site geometry as well as a tunnel connecting the bulk solvent to the copper site, through which only small molecules such as H2O, O2, and H2O2 can diffuse. Rearrangement of Cu-coordinating water molecules is necessary when binding the substrate and also provide a rationale for the experimentally observed C1 oxidative regiospecificity 744375 1.14.99.53 structure of the catalytic domain, residues 37-230, to 1.08 A resolution. The active site in is formed by residues His-37 and His-144 that coordinate the copper atom in a T-shaped geometry 745380 1.14.99.53 structures in the resting state and of a copper(II)-dioxo intermediate complex formed in the absence of substrate reveal pre-bound molecular oxygen adjacent to the active site. A conserved histidine is involved in promoting oxygen activation 744034 1.14.99.53 to 1.2 A resolution. Diffraction resolution and crystal morphology are improved by expression from a glycoengineered strain of Pichia pastoris 743966 1.14.99.53 to 1.3 A resolution 741336 1.14.99.53 to 1.85 A resolution, tri-modular enzyme containing a catalytic family AA10 LPMO module, a family 5 chitin-binding module, and a C-terminal unclassified module which displays tight and specific binding to chitin 740758