Modulation of Superoxide Dismutase Activity by Mercury, Lead, and Arsenic

Abhishek Kumar, Khushboo, Rukmani Pandey, Bechan Sharma

Research output: Contribution to journalArticlepeer-review

20 Scopus citations


Arsenic, mercury and lead are the environmental toxicants which exert their toxic effects through binding with certain proteins including their structures and functions. The toxicity of these heavy metal results is associated to its interaction with the metalloenzymes. They replace the essential metals required for normal biochemical functions of enzymes. The superoxide dismutase (SOD), a metalloenzyme, requires certain cofactors such as Cu2+ and Zn2+ for their optimal activity. However, the studies on the in vitro kinetic characterization of SOD from the rat liver cytosolic fraction have not been reported. The main objective of this study concerns the determination of the effect of three heavy metals such as arsenic, mercury, and lead on the activity of cytosolic SOD isolated from post nuclear supernatant (PNS) of rat liver. The activity of SOD was calculated using pyrogallol as a substrate. The stability and the sensitivity of enzyme activity were measured by assaying the enzyme activity at different temperature conditions. In order to determine the IC50 of the heavy metals, the enzyme activity was monitored in the presence of different concentrations of heavy metals. The values of all kinetic parameters including Km, Vmax, and Kcat were calculated by assaying SOD in the presence and absence of heavy metals. The results indicated that these heavy metals were able to significantly modulate the kinetic behavior of hepatic SOD. The data from present study could be utilized to develop suitable antidotes to mitigate the adverse effects of these heavy metals. [Figure not available: see fulltext.]

Original languageEnglish
Pages (from-to)654-661
Number of pages8
JournalBiological Trace Element Research
Issue number2
StatePublished - 1 Aug 2020
Externally publishedYes


  • Arsenic
  • Hepatotoxicity
  • Lead
  • Mercury
  • Superoxide dismutase


Dive into the research topics of 'Modulation of Superoxide Dismutase Activity by Mercury, Lead, and Arsenic'. Together they form a unique fingerprint.

Cite this