Abstract
Laccases are members of the blue multicopper oxidase family. These enzymes oxidize substrate molecules by accepting electrons at a mononuclear copper centre and transferring them to a trinuclear centre. Dioxygen binds to the trinuclear centre and following the transfer of four electrons is reduced to two molecules of water. The X-ray structure of a laccase from Cerrena maxima has been elucidated at 1.9 angstrom resolution using synchrotron data and the molecular replacement technique. The final refinement coefficients are R-cryst = 16.8% and R-free = 23.0%, with root mean square deviations on bond lengths and bond angles of 0.015 angstrom and 1.51 degrees, respectively. The type 1 copper centre has an isoleucine residue at the axial position and the "resting" state of the trinuclear centre comprises a single oxygen (OH) moiety asymmetrically disposed between the two type 3 copper ions and a water molecule attached to the type 2 ion. Several carbohydrate binding sites have been identified and the glycan chains appear to promote the formation of well-ordered crystals. Two tyrosine residues near the protein surface have been found in a nitrated state.
Original language | English |
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Pages (from-to) | 963-973 |
Number of pages | 11 |
Journal | Journal of Biological Inorganic Chemistry |
Volume | 11 |
DOIs | |
Publication status | Published - Nov 2006 |
Keywords
- laccase
- trinuclear copper site
- glycans
- nitrated tyrosine residues
- WHITE-ROT FUNGI
- CRYSTAL-STRUCTURE
- ANGSTROM RESOLUTION
- COPRINUS-CINEREUS
- CORIOLUS-HIRSUTUS
- ELECTRON-TRANSFER
- FULL COMPLEMENT
- COPPER PROTEINS
- NITRIC-OXIDE
- REDUCTION