Interaction of human DNA polymerase. beta. with ions of copper, lead, and cadmium

Journal Article · Wed Aug 01 04:00:00 EDT 1979 · Arch. Biochem. Biophys.; (United States)

DOI:https://doi.org/10.1016/0003-9861(79)90557-5· OSTI ID:5059088

Popenoe, E A; Schmaeler, M A

Under appropriate conditions, divalent copper, lead, and cadmium ions significantly inhibit human DNA polymerase ..beta.. (following accepted convention, the term DNA polymerase ..beta.. refers to the low-molecular-weight, 3 to 4 S DNA polymerase of eukaryotic cells) at concentrations below 10/sup -5/ M. Each metal showed apparent linear noncompetitive inhibition kinetics with respect to the template primer and the deoxynucleoside triphosphate substrate, indicating that complex formation with these components does not account for the inhibition. Apparently, neither lead nor cadmium inhibits by displacing required zinc atoms from the polymerase. The interaction of the metals with the enzyme can be reversed or prevented by EDTA or by thiol compounds, except that inhibition by cadmium ions can be reversed by monothiols but not by dithiols. The metals probably do not inhibit through reaction with thiol groups since the inhibition is not decreased by pretreating the enzyme with N-ethylmaleimide. Although divalent zinc is moderately inhibitory in manganese activated poly(dT) synthesis on a poly(dA) template, it can fill the requirement for a divalent metal ion and, under the conditions tested, is about 60% as effective as Mn/sup 2 +/.

• Research Organization: Brookhaven National Lab., Upton, NY
• DOE Contract Number: EY-76-C-02-0016
• OSTI ID: 5059088
• Journal Information: Arch. Biochem. Biophys.; (United States), Journal Name: Arch. Biochem. Biophys.; (United States) Journal Issue: 1 Vol. 196:1; ISSN ABBIA
• Country of Publication: United States
• Language: English

Related Subjects

550200 -- Biochemistry
560306* -- Chemicals Metabolism & Toxicology-- Man-- (-1987)
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
BIOCHEMICAL REACTION KINETICS
BIOCHEMISTRY
BIOSYNTHESIS
CADMIUM IONS
CHARGED PARTICLES
CHEMISTRY
COPPER IONS
DNA
ENZYMES
INHIBITION
IONS
KINETICS
LEAD IONS
MAMMALS
MAN
NUCLEIC ACIDS
ORGANIC COMPOUNDS
POLYMERASES
PRIMATES
REACTION KINETICS
SYNTHESIS
TOXICITY
VERTEBRATES