This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Makino, S.-I.
Right arrow Articles by Itoh, K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Makino, S.-I.
Right arrow Articles by Itoh, K.
Agricola
Right arrow Articles by Makino, S.-I.
Right arrow Articles by Itoh, K.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, December 2000, p. 5536-5539, Vol. 66, No. 12
0099-2240/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.

Does Enterohemorrhagic Escherichia coli O157:H7 Enter the Viable but Nonculturable State in Salted Salmon Roe?

Sou-Ichi Makino,1,* Tsutomu Kii,1 Hiroshi Asakura,1 Toshikazu Shirahata,1 Tetsuya Ikeda,2 Kouichi Takeshi,2 and Kikuji Itoh3

Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555,1 Hokkaido Institute of Public Health, Sapporo, Hokkaido 060-0819,2 and Graduate School of Agriculture and Life Science, The University of Tokyo, Tokyo 113-8657,3 Japan

Received 31 May 2000/Accepted 30 September 2000

An outbreak caused by salted salmon roe contaminated with enterohemorrhagic Escherichia coli O157 occurred in Japan in 1998. Since about 0.75 to 1.5 viable cells were estimated to cause infection, we presumed that O157 might enter the viable but nonculturable (VNC) state in salted salmon roe and consequently that viable cell numbers might be underestimated. Although patient-originating O157 cells could not grow on agar plates after 72 h of incubation in 13% NaCl, they were resuscitated in yeast extract broth, and more than 90% of the cells were shown to be viable by fluorescent staining, suggesting that almost all of them could enter the VNC state in NaCl water. Roe-originating O157 was resistant to NaCl because it could grow on agar after 72 h of incubation in NaCl water, but about 20% of cells appeared to enter the VNC state. Therefore, germfree mice were infected with O157 to examine the resuscitation of cells in the VNC state and the retention of pathogenicity. O157 that originated in roe, but not patients, killed mice and was isolated from the intestine. However, these isolates had become sensitive to NaCl. O157 cells of roe origin incubated in normal media also killed mice and were isolated from the intestine, but they also became transiently NaCl sensitive. We therefore propose that bacterial cells might enter the VNC state under conditions of stress, such as those encountered in vivo or in high salt concentrations, and then revive when those conditions have eased. If so, the VNC state in food is potentially dangerous from a public health viewpoint and may have to be considered at the time of food inspection. Finally, the establishment of a simple recovery system for VNC cells should be established.


* Corresponding author. Mailing address: Department of Veterinary Microbiology, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan. Phone and fax: 81-155-49-5386. E-mail: smakino{at}obihiro.ac.jp.


Applied and Environmental Microbiology, December 2000, p. 5536-5539, Vol. 66, No. 12
0099-2240/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.



This article has been cited by other articles:

  • Vora, G. J., Meador, C. E., Bird, M. M., Bopp, C. A., Andreadis, J. D., Stenger, D. A. (2005). Microarray-based detection of genetic heterogeneity, antimicrobial resistance, and the viable but nonculturable state in human pathogenic Vibrio spp.. Proc. Natl. Acad. Sci. USA 102: 19109-19114 [Abstract] [Full Text]  
  • Dodd, C. C., Sanderson, M. W., Sargeant, J. M., Nagaraja, T. G., Oberst, R. D., Smith, R. A., Griffin, D. D. (2003). Prevalence of Escherichia coli O157 in Cattle Feeds in Midwestern Feedlots. Appl. Environ. Microbiol. 69: 5243-5247 [Abstract] [Full Text]  
  • Ritchie, J. M., Campbell, G. R., Shepherd, J., Beaton, Y., Jones, D., Killham, K., Artz, R. R. E. (2003). A Stable Bioluminescent Construct of Escherichia coli O157:H7 for Hazard Assessments of Long-Term Survival in the Environment. Appl. Environ. Microbiol. 69: 3359-3367 [Abstract] [Full Text]  
  • Makino, S.-I., Tobe, T., Asakura, H., Watarai, M., Ikeda, T., Takeshi, K., Sasakawa, C. (2003). Distribution of the Secondary Type III Secretion System Locus Found in Enterohemorrhagic Escherichia coli O157:H7 Isolates among Shiga Toxin-Producing E. coli Strains. J. Clin. Microbiol. 41: 2341-2347 [Abstract] [Full Text]  
  • Kolling, G. L., Matthews, K. R. (2001). Examination of Recovery In Vitro and In Vivo of Nonculturable Escherichia coli O157:H7. Appl. Environ. Microbiol. 67: 3928-3933 [Abstract] [Full Text]