Restoration of culturability of starvation-stressed and low-temperature-stressed Escherichia coli O157 cells by using H2O2-degrading compounds

Arch Microbiol. 1999 Jul;172(1):63-7. doi: 10.1007/s002030050741.


Late-exponential-phase cells of Escherichia coli O157:H- strain E32511/HSC became nonculturable in sterilized distilled water microcosms at 4 degrees C. Plate counts declined from 3 x 10(6) to less than 0.1 CFU/ml in about 21 days. However, when samples of microcosms at 21 days were inoculated onto an agar medium amended with catalase or nonenzyme peroxide-degrading compounds such as sodium pyruvate or alpha-ketoglutaric acid, plate counts increased to 10(4)-10(5) CFU/ml within 48 h. The proposed mode of action of the catalase or pyruvate is via the degradation of the metabolic by-product H2O2, rather than through supplementation of a required nutrient in the recovery of nonculturable cells. Our studies were based on the assumption that E32511/HSC strain responds to starvation and a low temperature by entering a nonculturable state and that the correction of oxidative stress upon the inoculation of bacteria on agar plates promotes recovery of nonculturable cells.

MeSH terms

  • Catalase
  • Cold Temperature
  • Colony Count, Microbial
  • Culture Media / chemistry
  • Escherichia coli O157 / growth & development*
  • Escherichia coli O157 / metabolism*
  • Hydrogen Peroxide / metabolism*
  • Ketoglutaric Acids
  • Pyruvates


  • Culture Media
  • Ketoglutaric Acids
  • Pyruvates
  • Hydrogen Peroxide
  • Catalase