Expression of major cold shock proteins and genes by Yersinia enterocolitica in synthetic medium and foods Article

Annamalai, T, Venkitanarayanan, K. (2005). Expression of major cold shock proteins and genes by Yersinia enterocolitica in synthetic medium and foods . JOURNAL OF FOOD PROTECTION, 68(11), 2454-2458. 10.4315/0362-028X-68.11.2454

cited authors

  • Annamalai, T; Venkitanarayanan, K

abstract

  • Yersinia enterocolitica is a psychrotrophic foodborne pathogen that has been implicated in outbreaks of foodborne illness involving cold-stored foods, especially milk and pork. A major mechanism bacteria use to adapt to cold is expression of cold shock proteins. The objective of this research was to study the expression of major cold shock proteins of Y. enterocolitica in Luria-Bertani (LB) broth, milk, and pork following a temperature downshift from 30 to 4°C. Y. enterocolitica was inoculated into 10 ml of LB broth, sterile skim milk, or pork, and the samples were stored at 4deg;C (cold shock) or 30°C (control) for 0, 4, 8, 12, and 24 h. At each sampling time, total protein and total RNA were extracted from Y. enterocolitica harvested from LB broth, milk, and pork and subjected to two-dimensional gel electrophoresis and dot blot analysis. Two major cold shock proteins (CspA1 and CspA2) of ∼7 kDa and their genes were expressed by Y. enterocolitica following cold shock. However, the CspA1 and CspA2 proteins were not expressed by Y. enterocolitica at 30°C. Y. enterocolitica CspA1 and CspA2 were observed as early as 2 h of cold shock in cultures from LB broth and milk and at 8 h of cold shock in cultures from pork. Copyright ©, International Association for Food Protection.

publication date

  • January 1, 2005

published in

Digital Object Identifier (DOI)

start page

  • 2454

end page

  • 2458

volume

  • 68

issue

  • 11