Inhibitory effects of Lactobacillus acidophilus lysates on the cytotoxic activity of shiga-like toxin 2 produced from Escherichia coli O157: H7

Y. Kim, K. S. Han, J. Y. Imm, S. Oh, Seungkwon You, S. Park, Sae Hun Kim

Research output: Contribution to journalArticle

19 Citations (Scopus)


Aims: The purpose of this study was to characterize the degree to which four cell lysates obtained from Lactobacillus acidophilus strains affected the cytotoxic activity of Escherichia coli O157:H7 in vitro and in vivo. Methods and Results: In a cytotoxic inhibition test that used 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide and toxin-binding ELISA assays, the activity of shiga-like toxin 2 (Stx-2) was inhibited profoundly by the cell lysates (10 mg ml-1) from two strains of L. acidophilus A4 and 30SC (>85% of survival rates compared with the control) among the five strains tested. In particular, a significant decline in the virulence level of E. coli O157:H7, under the presence of the cell lysates of L. acidophilus A4, was observed by killing assay of Caenorhabditis elegans in vivo model. Conclusions: According to our results, L. acidophilus strains might be capable of attenuating the virulence of Stx-2 produced from E. coli O157:H7. Significance and Impact of the Study: The cell lysates of L. acidophilus can be applied to a variety of foods, and can be used as adjuncts for the inhibition of Stx-2-mediated cytotoxicity.

Original languageEnglish
Pages (from-to)502-507
Number of pages6
JournalLetters in Applied Microbiology
Issue number5
Publication statusPublished - 2006 Nov 1



  • Caenorhabditis elegans
  • Cytotoxicity
  • Escherichia coli O157:H7
  • Lactobacillus acidophilus
  • Shiga-like toxin 2

ASJC Scopus subject areas

  • Applied Microbiology and Biotechnology
  • Water Science and Technology
  • Fluid Flow and Transfer Processes
  • Microbiology
  • Ecology

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