Crystal structure of plant pectin methylesterase.
Pectin is a principal component in the primary cell wall of plants. During cell development, pectin is modified by pectin methylesterases to give different properties to the cell wall. This report describes the first crystal structure of a plant pectin methylesterase. The beta-helical structure embodies a central cleft, lined by several aromatic residues, that has been deduced to be suitable for pectin binding. The active site is found at the center of this cleft where Asp157 is suggested to act as the nucleophile, Asp136 as an acid/base and Gln113/Gln135 to form an anion hole to stabilize the transition state.
Johansson
Kenth
K
Department of Molecular Biology, Swedish University of Agricultural Sciences, S-751 24 Uppsala, Sweden.
El-Ahmad
Mustapha
M
Friemann
Rosmarie
R
Jörnvall
Hans
H
Markovic
Oskar
O
Eklund
Hans
H
D001665:Binding Sites / Q000502:physiology; D002265:Carboxylic Ester Hydrolases / Q000737:chemistry*; D002384:Catalysis; D018360:Crystallography, X-Ray; D018552:Daucus carota / Q000201:enzymology*; D016974:Dickeya chrysanthemi / Q000201:enzymology; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry; D017433:Protein Structure, Secondary / Q000502:physiology; D017434:Protein Structure, Tertiary / Q000502:physiology; D017386:Sequence Homology, Amino Acid
D010940:Plant Proteins; D002265:Carboxylic Ester Hydrolases; C022323:pectinesterase