Inactivation of beef plasma amine oxidase by sulfide

Journal Article · Thu Mar 01 04:00:00 EST 1984 · J. Biol. Chem.; (United States)

OSTI ID:6444127

Dooley, D M; Cote, C E

Sulfide irreversibly inactivates beef plasma amine oxidase in a time-dependent reaction. Mercaptoacetic acid and 2-mercaptoethanol do not inactivate the enzyme. The sulfide complex displayed an intense absorption band at 360 nm (element of = 6000 M/sup -1/ cm/sup -1/, per mol of copper) that is assigned as sigmaS ..-->.. Cu(II) ligand to metal charge-transfer transition. However, this band slowly decreased in intensity; the final spectrum resembles the spectrum of the dithionite-reduced enzyme. Bleaching at approx. 450-500 nm specifically indicates that the organic cofactor is reduced. EPR parameters for the sulfide complex differ significantly from those observed for the native amine oxidase. Superhyperfine structure, attributable to coordinated nitrogens, is clearly evident. Time-dependent reduction of Cu(II) that parallels the kinetics and absorbance changes was also observed by EPR. The amine oxidaseazide complex was inactivated by sulfide at a considerably slower rate than the resting enzyme. Since azide is known to coordinate to Cu(II) in beef plasma amine oxidase, the data strongly suggest that enzyme-bound copper is the site of action for inhibition by sulfide.

• Research Organization: Amherst Coll., MA
• OSTI ID: 6444127
• Journal Information: J. Biol. Chem.; (United States), Journal Name: J. Biol. Chem.; (United States) Vol. 259:5; ISSN JBCHA
• Country of Publication: United States
• Language: English

Related Subjects

560301* -- Chemicals Metabolism & Toxicology-- Cells-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
BIOLOGICAL EFFECTS
BIOLOGICAL MATERIALS
BLOOD
BLOOD PLASMA
BODY FLUIDS
CATTLE
CHALCOGENIDES
CHEMICAL REACTIONS
COPPER
DOMESTIC ANIMALS
ELEMENTS
ENZYMES
INACTIVATION
LIGANDS
MAMMALS
MATERIALS
METALS
OXIDOREDUCTASES
REDOX REACTIONS
RUMINANTS
SPECTROSCOPY
SULFIDES
SULFUR COMPOUNDS
TIME DEPENDENCE
TRANSITION ELEMENTS
VERTEBRATES