This scanning
electron microscope image shows the characteristic spiral, or corkscrew, shape
of Campylobacter jejuni cells and related structures.
Campylobacter bacteria are the number-one cause of food-related
gastrointestinal illness in the United States. Click the image for more
information about it. |
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New Campylobacter-Detecting Medium
Licensed
By Sharon Durham October 16, 2007
A quicker, simpler way to distinguish between Campylobacter
species has now been licensed for manufacture by two U.S. companies. The new
culture medium called Campy-Cefex is specifically designed to detect and
differentiate C. jejuni and C. coli mixtures of
food-contaminating microbes. These two bacteria are important causes of
foodborne illness.
Agricultural Research Service (ARS) microbiologist
Norman
Stern, with the ARS Poultry Microbiological Safety Research Unit (PMSRU)
in Athens, Ga., began developing the new medium in 1987. Thats when he
traveled to Poland to work with researchers Boleslaw Wojton and Kris Kwiatek at
the Veterinary Research
Institute in Pulawy, Poland.
They worked cooperatively to characterize Campylobacter
contamination in poultry. Previous media for detection of Campylobacter
relied upon the use of new antibiotics that were unavailable in Poland. In
developing the medium, Stern used the only two he had brought with
himcycloheximide and cefoperazone.
Surprisingly, the two compounds provided superior efficacy, not only
for growing Campylobacter in a culture, but also for repressing the
growth of most other microorganisms. The additional antibiotics previously
employed with other Campylobacter media were not needed.
A patent for the Campy-Cefex culture medium was awarded in 1999 to
Stern, with Wojton and Kwiatek listed as co-inventors. Now licensing agreements
to produce the new culture medium have been entered into with
Becton Dickinson and Company, Franklin Lakes,
N.J., and Neogen Corporation, Lansing,
Mich.
Campy-Cefex selects for Campylobacter among competing flora in
a sample, cultivating colonies that resemble tiny water droplets. From these,
microbiologists can estimate the level of Campylobacter contamination in
the sample.
PMRSUs technical staff trained several
U.S. Department of Agriculture regulatory
agency employees in the use of the media and techniques for
Campylobacter enumeration for research studies.
ARS is the USDAs chief scientific research agency.