Microbial genotoxicity bioreporters based on sulA activation

Alva Biran, Hadar Ben Yoav, Sharon Yagur-Kroll, Rami Pedahzur, Sebastian Buchinger, Yosi Shacham-Diamand, Georg Reifferscheid, Shimshon Belkin*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

29 Scopus citations

Abstract

A bacterial genotoxicity reporter strain was constructed in which the tightly controlled strong promoter of the Escherichia coli SOS response gene sulA was fused to the alkaline phosphatase-coding phoA reporter gene. The bioreporter responded in a dose-dependent manner to three model DNA-damaging agents-hydrogen peroxide, nalidixic acid (NA), and mitomycin C (MMC)-detected 30-60 min after exposure. Detection thresholds were 0.15 μM for MMC, 7.5 μM for nalidixic acid, and approximately 50 μM for hydrogen peroxide. A similar response to NA was observed when the bioreporter was integrated into a specially designed, portable electrochemical detection platform. Reporter sensitivity was further enhanced by single and double knockout mutations that enhanced cell membrane permeability (rfaE) and inhibited DNA damage repair mechanisms (umuD, uvrA). The rfaE mutants displayed a five- and tenfold increase in sensitivity to MMC and NA, respectively, while the uvrA mutation was advantageous in the detection of hydrogen peroxide. A similar sensitivity was displayed by the double rfaE/uvrA mutant when challenged with the pre-genotoxic agents 2-amino-3-methylimidazo[4,5-f]quinoline and 2-aminoanthracene following metabolic activation with an S9 mammalian liver fraction.

Original languageEnglish
Pages (from-to)3013-3024
Number of pages12
JournalAnalytical and Bioanalytical Chemistry
Volume400
Issue number9
DOIs
StatePublished - Jul 2011

Keywords

  • Bioluminescence
  • Electrochemistry
  • Environmental monitoring
  • Escherichia coli
  • Genotoxicity detection
  • Whole-cell biosensors

Fingerprint

Dive into the research topics of 'Microbial genotoxicity bioreporters based on sulA activation'. Together they form a unique fingerprint.

Cite this