Kp. Francis et al., DISCRIMINATION OF PSYCHROTROPHIC AND MESOPHILIC STRAINS OF THE BACILLUS-CEREUS GROUP BY PCR TARGETING OF MAJOR COLD SHOCK PROTEIN GENES, Applied and environmental microbiology, 64(9), 1998, pp. 3525-3529
Detection of psychrotrophic strains (those able to grow at or below 7
degrees C) of the Bacillus cereus group (Bacillus cereus, Bacillus thu
ringiensis, and Bacillus mycoides) in food products is at present extr
emely slow with conventional microbiology. This is due to an inability
to discriminate these cold-adapted strains from their mesophilic coun
terparts (those able to grow only above 7 degrees C) by means other th
an growth at low temperature, which takes 5 to 10 days for detection.
Here we report the development of a single PCR assay that, using major
cold shock protein-specific primers and appropriate annealing tempera
tures, is capable of both rapidly identifying bacteria of the B, cereu
s group and discriminating between psychrotrophic and mesophilic strai
ns. It is intended that this development help to more accurately predi
ct the shelf life of refrigerated pasteurized food and dairy products
and to reduce the incidence of food poisoning by psychrotrophic strain
s of the B, cereus group.