Radiation resistance of virulence plasmid-containing and plasmid-less Yersinia enterocolitica.
Yersinia enterocolitica, a foodborne pathogen, can be eliminated from meat by ionizing radiation. Y. enterocolitica sometimes contains a 70-kb virulence plasmid that encodes genes for a type III secretion channel and host immune suppression factors. The radiation resistance of virulence plasmid-containing and plasmid-less Y. enterocolitica was determined. Four Y. enterocolitica serotypes containing (i) the large virulence plasmid, and (ii) their plasmid-less derivatives were inoculated into raw ground pork, which was then vacuum packed and irradiated at 4 degrees C to doses of 0.2, 0.4, 0.6, 0.8, and 1.0 kGy. The D10-value, the radiation dose required to reduce the number of viable Y. enterocolitica by 90%, was not dependent on the presence or absence of the virulence plasmid, but it did differ among the four Y. enterocolitica serotypes.
Sommers
Christopher H
CH
US Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, Wyndmoor, Pennsylvania 19038, USA. csommers@arserrc.gov
Novak
John S
JS
D000818:Animals; D004307:Dose-Response Relationship, Radiation; D005514:Food Irradiation; D008461:Meat Products / Q000382:microbiology*; D010957:Plasmids; D016133:Polymerase Chain Reaction; D013552:Swine; D014774:Virulence; D015008:Yersinia enterocolitica / Q000472:pathogenicity / Q000502:physiology* / Q000528:radiation effects*