Hydrogen tunneling in peptidylglycine alpha-hydroxylating monooxygenase.
The temperature dependence of the primary and secondary intrinsic isotope effects for the C-H bond cleavage catalyzed by peptidylglycine alpha-hydroxylating monooxygenase has been determined. Analysis of the magnitude and Arrhenius behavior of the intrinsic isotope effects provides strong evidence for the use of tunneling as a primary catalytic strategy for this enzyme. Modeling of the isotope effect data allows for a comparison to the hydrogen transfer catalyzed by soybean lipoxygenase in terms of environmental reorganization energy and frequency of the protein vibration that controls the hydrogen transfer.
Francisco
Wilson A
WA
Department of Chemistry, University of California, Berkeley, California 94720-1460, USA.
Knapp
Michael J
MJ
Blackburn
Ninian J
NJ
Klinman
Judith P
JP
D003903:Deuterium / Q000737:chemistry / Q000378:metabolism; D005998:Glycine / Q000737:chemistry / Q000378:metabolism; D006859:Hydrogen / Q000737:chemistry* / Q000378:metabolism; D007700:Kinetics; D006899:Mixed Function Oxygenases / Q000737:chemistry* / Q000378:metabolism; D009097:Multienzyme Complexes / Q000737:chemistry* / Q000378:metabolism; D013696:Temperature; D013816:Thermodynamics
D009097:Multienzyme Complexes; D006859:Hydrogen; D003903:Deuterium; D006899:Mixed Function Oxygenases; C035189:peptidylglycine monooxygenase; D005998:Glycine