1a65: Difference between revisions

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==Overview==
==Overview==
Laccase catalyses the oxidation of a variety of organic substrates coupled, to the reduction of oxygen to water. It is widely believed to be the, simplest representative of the ubiquitous blue multi-copper oxidase, family. Laccase is implicated in a wide spectrum of biological activities, and, in particular, plays a key role in morphogenesis, development and, lignin metabolism in fungi and plants. The structure of laccase from the, fungus Coprinus cinereus has been determined by X-ray crystallography at a, resolution of 2.2 A. Laccase is a monomer composed of three, cupredoxin-like beta-sandwich domains, similar to that found in ascorbate, oxidase. In contrast to ascorbate oxidase, however, the mononuclear type-1, Cu site lacks the axial methionine ligand and so exhibits trigonal planar, coordination, consistent with its elevated redox potential. Crucially, the, structure is trapped in a Cu depleted form in which the putative type-2 Cu, atom is completely absent, but in which the remaining type-1 and type-3 Cu, sites display full occupancy. Type-2 Cu depletion has unexpected, consequences for the coordination of the remaining type-3 Cu atoms.
Laccase catalyses the oxidation of a variety of organic substrates coupled to the reduction of oxygen to water. It is widely believed to be the simplest representative of the ubiquitous blue multi-copper oxidase family. Laccase is implicated in a wide spectrum of biological activities and, in particular, plays a key role in morphogenesis, development and lignin metabolism in fungi and plants. The structure of laccase from the fungus Coprinus cinereus has been determined by X-ray crystallography at a resolution of 2.2 A. Laccase is a monomer composed of three cupredoxin-like beta-sandwich domains, similar to that found in ascorbate oxidase. In contrast to ascorbate oxidase, however, the mononuclear type-1 Cu site lacks the axial methionine ligand and so exhibits trigonal planar coordination, consistent with its elevated redox potential. Crucially, the structure is trapped in a Cu depleted form in which the putative type-2 Cu atom is completely absent, but in which the remaining type-1 and type-3 Cu sites display full occupancy. Type-2 Cu depletion has unexpected consequences for the coordination of the remaining type-3 Cu atoms.


==About this Structure==
==About this Structure==
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[[Category: type-2 copper depleted]]
[[Category: type-2 copper depleted]]


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