Effect of mercury, cadmium, nickel, chromium and zinc on kinetic properties of NADPH-cytochrome P450 reductase purified from leaping mullet (Liza saliens)

Bozcaarmutlu, A; Arinc, E

HERO ID

1848002

Reference Type

Journal Article

Year

2007

Language

English

PMID

17113746

HERO ID 1848002
In Press No
Year 2007
Title Effect of mercury, cadmium, nickel, chromium and zinc on kinetic properties of NADPH-cytochrome P450 reductase purified from leaping mullet (Liza saliens)
Authors Bozcaarmutlu, A; Arinc, E
Journal Toxicology In Vitro
Volume 21
Issue 3
Page Numbers 408-416
Abstract Information on the mechanism of metal ion inhibition of NADPH-cytochrome P450 reductase is limited. The purpose of the present paper was to elucidate in vitro effect of Hg(+2), Cd(+2), Ni(+2), Cr(+3) and Zn(+2) ions on the purified mullet NADPH-cytochrome P450 reductase. NADPH-cytochrome P450 reductase was purified from detergent-solubilized liver microsomes from leaping mullet (Liza saliens). All of the metal ions caused inhibition of the enzyme activity except Zn(+2). At 50 microM metal concentration, Hg(+2) inhibited the cytochrome P450 reductase activity completely (100%), while, at the same concentrations, Cd(+2), Cr(+3) and Ni(+2) caused 66%, 65% and 37% inhibition, respectively. At 50 microM metal concentration, Zn(+2) had no apparent effect on cytochrome P450 reductase activity. The IC(50) values of HgCl(2), CrCl(3), CdCl(2) and NiCl(2) were estimated to be 0.07 microM, 24 microM, 33 microM and 143 microM, respectively. Of the metal ions tested, Hg(+2) exhibited much higher inhibitory effect at lower concentrations, so it was evidently a more potent inhibitor than the others. All four metal ions displayed noncompetitive type of inhibition mechanism for the purified reductase as analyzed by Dixon plot. K(i) values of Hg(+2), Cr(+3), Cd(+2), and Ni(+2) were calculated from Dixon plots as 0.048 microM, 18 microM, 73 microM and 329 microM, respectively.
Doi 10.1016/j.tiv.2006.10.002
Pmid 17113746
Wosid WOS:000246548200011
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English
Keyword noncompetitive inhibition; leaping mullet (Liza saliens); NADPH-cytochrome p450 reductase; mercury; cadmium; nickel; chromium; zinc