Bovine plasma amine oxidase (PAO) oxidizes substrate by a proton activation mechanism
Abstract
PAO catalyzes the oxidative deamination of amines to aldehydes, concomitant with a 2e/sup -/ reduction of O/sub 2/ to H/sub 2/O/sub 2/. Several investigators have proposed recently that the organic cofactor in PAO is pyrroloquinoline quinone (PQQ), hitherto seen exclusively in prokaryotes. The structure and properties of PQQ predict first, that substrate and PAO will form a covalent adduct and second, that substrate will be oxidized via proton abstraction. In earlier studies from this laboratory, steady state isotope effects, in conjunction with an intrinsic isotope effect, have been shown to provide microscopic rate constants from complex mechanisms. In this study, V, D/sub V/, V/K and /sup D/(V/K) have been measured for the oxidation of a series of nine ring-substituted benzylamines and (1-/sup 2/H/sub 2/)-benzylamines with PAO. The series of substrates was chosen to minimize collinearity in the electronic and hydrophobic properties of ring substituents. Computed rate constants for the C-H bond cleavage step indicate a strong correlation with electron withdrawing substituents, rho = 1.3, confirming the formation of a discrete carbanion intermediate upon substrate activation. Additional studies are in progress, with the objective of trapping and characterizing the putative adduct between PAO and substrates.
- Authors:
- Publication Date:
- Research Org.:
- Univ. of California, Berkeley
- OSTI Identifier:
- 5272237
- Report Number(s):
- CONF-8606151-
Journal ID: CODEN: FEPRA; TRN: 86-031448
- Resource Type:
- Conference
- Journal Name:
- Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)
- Additional Journal Information:
- Journal Volume: 45:6; Conference: 76. annual meeting of the Federation of American Society for Experimental Biology, Washington, DC, USA, 8 Jun 1986
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 59 BASIC BIOLOGICAL SCIENCES; AMINES; DEAMINATION; OXIDOREDUCTASES; ENZYME ACTIVITY; ALDEHYDES; BLOOD PLASMA; CATTLE; DEUTERIUM; ELECTRONS; PROTONS; SUBSTRATES; TRACER TECHNIQUES; ANIMALS; BARYONS; BIOLOGICAL MATERIALS; BLOOD; BODY FLUIDS; CHEMICAL REACTIONS; DOMESTIC ANIMALS; ELEMENTARY PARTICLES; ENZYMES; FERMIONS; HADRONS; HYDROGEN ISOTOPES; ISOTOPE APPLICATIONS; ISOTOPES; LEPTONS; LIGHT NUCLEI; MAMMALS; MATERIALS; NUCLEI; NUCLEONS; ODD-ODD NUCLEI; ORGANIC COMPOUNDS; RUMINANTS; STABLE ISOTOPES; VERTEBRATES; 550201* - Biochemistry- Tracer Techniques
Citation Formats
Hartmann, C, and Klinman, J P. Bovine plasma amine oxidase (PAO) oxidizes substrate by a proton activation mechanism. United States: N. p., 1986.
Web.
Hartmann, C, & Klinman, J P. Bovine plasma amine oxidase (PAO) oxidizes substrate by a proton activation mechanism. United States.
Hartmann, C, and Klinman, J P. 1986.
"Bovine plasma amine oxidase (PAO) oxidizes substrate by a proton activation mechanism". United States.
@article{osti_5272237,
title = {Bovine plasma amine oxidase (PAO) oxidizes substrate by a proton activation mechanism},
author = {Hartmann, C and Klinman, J P},
abstractNote = {PAO catalyzes the oxidative deamination of amines to aldehydes, concomitant with a 2e/sup -/ reduction of O/sub 2/ to H/sub 2/O/sub 2/. Several investigators have proposed recently that the organic cofactor in PAO is pyrroloquinoline quinone (PQQ), hitherto seen exclusively in prokaryotes. The structure and properties of PQQ predict first, that substrate and PAO will form a covalent adduct and second, that substrate will be oxidized via proton abstraction. In earlier studies from this laboratory, steady state isotope effects, in conjunction with an intrinsic isotope effect, have been shown to provide microscopic rate constants from complex mechanisms. In this study, V, D/sub V/, V/K and /sup D/(V/K) have been measured for the oxidation of a series of nine ring-substituted benzylamines and (1-/sup 2/H/sub 2/)-benzylamines with PAO. The series of substrates was chosen to minimize collinearity in the electronic and hydrophobic properties of ring substituents. Computed rate constants for the C-H bond cleavage step indicate a strong correlation with electron withdrawing substituents, rho = 1.3, confirming the formation of a discrete carbanion intermediate upon substrate activation. Additional studies are in progress, with the objective of trapping and characterizing the putative adduct between PAO and substrates.},
doi = {},
url = {https://www.osti.gov/biblio/5272237},
journal = {Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)},
number = ,
volume = 45:6,
place = {United States},
year = {Thu May 01 00:00:00 EDT 1986},
month = {Thu May 01 00:00:00 EDT 1986}
}