Open AccessComparative Effects of Osmotic, Sodium Nitrite-Induced, and pH-Induced Stress on Growth and Survival of Clostridium perfringens Type A Isolates Carrying Chromosomal or Plasmid-Borne Enterotoxin Genes
Author(s) -
Jihong Li,
Bruce A. McClane
Publication year - 2006
Publication title -
applied and environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.552
H-Index - 324
eISSN - 1070-6291
pISSN - 0099-2240
DOI - 10.1128/aem.01911-06
Subject(s) - clostridium perfringens , microbiology and biotechnology , biology , enterotoxin , plasmid , spore , gene , bacteria , food poisoning , toxin , strain (injury) , polymyxin , genetics , escherichia coli , antibiotics , anatomy
About 1 to 2% ofClostridium perfringens isolates carry the enterotoxin gene (cpe ) necessary for causingC. perfringens type A food poisoning. While thecpe gene can be either chromosomal or plasmid borne, food poisoning isolates usually carry a chromosomalcpe gene. Previous studies have linked this association between chromosomalcpe isolates (i.e., C-cpe isolates) and food poisoning, at least in part, to both the spores and vegetative cells of C-cpe isolates being particularly resistant to high and low temperatures. The current study now reveals that the resistance phenotype of C-cpe isolates extends beyond temperature resistance to also include, for both vegetative cells and spores, enhanced resistance to osmotic stress (from NaCl) and nitrites. However, by omitting one outlier isolate, no significant differences in pH sensitivity were detected between the spores or vegetative cells of C-cpe isolates versus isolates carrying a plasmid-bornecpe gene. These results indicate that both vegetative cells and spores of C-cpe isolates are unusually resistant to several food preservation approaches in addition to temperature extremes. The broad-spectrum nature of the C-cpe resistance phenotype suggests these bacteria may employ multiple mechanisms to persist and grow in foods prior to their transmission to humans.