TY - JOUR
T1 - Docking simulation and competitive experiments validate the interaction between the 2, 5-xylidine inhibitor and rigidoporus lignosus laccase
AU - Cambria, Maria Teresa
AU - Di Marino, Daniele
AU - Falconi, Mattia
AU - Garavaglia, Silvia
AU - Cambria, Antonio
PY - 2010/2
Y1 - 2010/2
N2 - Laccases are polyphenol oxidases which oxidize a broad range of reducing substrates, preferably phenolic compounds, and their use in biotechnological applications is increasing. Recently, the first X-ray structure of active laccase from white rot fungus Rigidoporus lignosus has been reported containing a full complement of copper ions. Comparison among selected fungal laccases of known 3D structure has shown that the Rigidoporus lignosus laccase has a very high similarity with the Trametes versicolor laccase that, being co-crystallized with 2, 5-xylidine, shows a well defined binding pocket for the substrate. Global sequence alignment between Rigidoporus lignosus and Trametes versicolor laccases shows 73% of identity but, surprisingly, there is no identity and neither conservative substitutions between the residues composing the loops directly contacting the 2, 5-xylidine. Moreover the structural alignment of these two enzymes identifies in these loops a striking structural similarity proposing the question if 2, 5-xylidine may bind in same enzyme pocket. Here we report the protein-ligand docking simulation of 3D structure of Rigidoporus lignosus laccase and 2, 5-xylidine. Docking simulation analyses show that spatial conformation of the two 2, 5-xylidine binding pockets, despite differences in the residues directly contacting the ligand, may arrange a similar pocket that allows a comparable accommodation of the inhibitor. To validate these results the binding of 2, 5-xylidine in the substrate cavity has been confirmed by kinetic competitive experiments.
AB - Laccases are polyphenol oxidases which oxidize a broad range of reducing substrates, preferably phenolic compounds, and their use in biotechnological applications is increasing. Recently, the first X-ray structure of active laccase from white rot fungus Rigidoporus lignosus has been reported containing a full complement of copper ions. Comparison among selected fungal laccases of known 3D structure has shown that the Rigidoporus lignosus laccase has a very high similarity with the Trametes versicolor laccase that, being co-crystallized with 2, 5-xylidine, shows a well defined binding pocket for the substrate. Global sequence alignment between Rigidoporus lignosus and Trametes versicolor laccases shows 73% of identity but, surprisingly, there is no identity and neither conservative substitutions between the residues composing the loops directly contacting the 2, 5-xylidine. Moreover the structural alignment of these two enzymes identifies in these loops a striking structural similarity proposing the question if 2, 5-xylidine may bind in same enzyme pocket. Here we report the protein-ligand docking simulation of 3D structure of Rigidoporus lignosus laccase and 2, 5-xylidine. Docking simulation analyses show that spatial conformation of the two 2, 5-xylidine binding pockets, despite differences in the residues directly contacting the ligand, may arrange a similar pocket that allows a comparable accommodation of the inhibitor. To validate these results the binding of 2, 5-xylidine in the substrate cavity has been confirmed by kinetic competitive experiments.
UR - http://www.scopus.com/inward/record.url?scp=75149114199&partnerID=8YFLogxK
U2 - 10.1080/07391102.2010.10507334
DO - 10.1080/07391102.2010.10507334
M3 - Article
SN - 0739-1102
VL - 27
SP - 501
EP - 509
JO - Journal of Biomolecular Structure and Dynamics
JF - Journal of Biomolecular Structure and Dynamics
IS - 4
ER -