title: Activity and molecular dynamics relationship within the family of human cholinesterases.
abstract: The temperature dependence of the dynamics of recombinant human acetylcholinesterase (hAChE) and plasma human butyrylcholinesterase (hBChE) is examined using elastic incoherent neutron scattering. These two enzymes belong to the same family and present 50% amino acid sequence identity. However, significantly higher flexibility and catalytic activity of hAChE when compared to the ones of hBChE are measured. At the same time, the average height of the potential barrier to the motions is increased in the hBChE, e.g. more thermal energy is needed to cross it in the latter case, which might be the origin of the increase in activation energy and the reduction in the catalytic rate of hBChE observed experimentally. These results suggest that the motions on the picosecond timescale may act as a lubricant for those associated with activity occurring on a slower millisecond timescale.
authors.affiliation: Université Joseph Fourier, UFR PhITEM, F-38041 Grenoble Cédex 9, France. peters@ill.fr.
authors.forename: Judith
authors.initials: J
authors.lastname: Peters
authors.forename: Marie
authors.initials: M
authors.lastname: Trovaslet
authors.forename: Marcus
authors.initials: M
authors.lastname: Trapp
authors.forename: Florian
authors.initials: F
authors.lastname: Nachon
authors.forename: Flynn
authors.initials: F
authors.lastname: Hill
authors.forename: Etienne
authors.initials: E
authors.lastname: Royer
authors.forename: Frank
authors.initials: F
authors.lastname: Gabel
authors.forename: Lambert
authors.initials: L
authors.lastname: van Eijck
authors.forename: Patrick
authors.initials: P
authors.lastname: Masson
authors.forename: Moeava
authors.initials: M
authors.lastname: Tehei
mesh_terms: D000110:Acetylcholinesterase / Q000737:chemistry / Q000378:metabolism*; D002091:Butyrylcholinesterase / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D056004:Molecular Dynamics Simulation; D011487:Protein Conformation; D013696:Temperature
chemical_list: D000110:Acetylcholinesterase; D002091:Butyrylcholinesterase