Bacterial toxicity of potassium tellurite: Unveiling an ancient enigma

José M. Pérez, Iván L. Calderón, Felipe A. Arenas, Derie E. Fuentes, Gonzalo A. Pradenas, Eugenia L. Fuentes, Juan M. Sandoval, Miguel E. Castro, Alex O. Elías, Claudio C. Vásquez

Research output: Contribution to journalArticlepeer-review

171 Scopus citations


Biochemical, genetic, enzymatic and molecular approaches were used to demonstrate, for the first time, that tellurite (TeO3 2-) toxicity in E. coli involves superoxide formation. This radical is derived, at least in part, from enzymatic TeO32- reduction. This conclusion is supported by the following observations made in K2TeO3-treated E. coli BW25113: i) induction of the ibpA gene encoding for the small heat shock protein IbpA, which has been associated with resistance to superoxide, ii) increase of cytoplasmic reactive oxygen species (ROS) as determined with ROS-specific probe 2′7′-dichlorodihydrofluorescein diacetate (H2DCFDA), iii) increase of carbonyl content in cellular proteins, iv) increase in the generation of thiobarbituric acid-reactive substances (TBARs), v) inactivation of oxidative stress-sensitive [Fe-S] enzymes such as aconitase, vi) increase of superoxide dismutase (SOD) activity, vii) increase of sodA, sodB and soxS mRNA transcription, and viii) generation of superoxide radical during in vitro enzymatic reduction of potassium tellurite.

Original languageEnglish (US)
Article numbere211
JournalPloS one
Issue number2
StatePublished - Feb 14 2007
Externally publishedYes

ASJC Scopus subject areas

  • General


Dive into the research topics of 'Bacterial toxicity of potassium tellurite: Unveiling an ancient enigma'. Together they form a unique fingerprint.

Cite this