Novak J S, Juneja V K, McClane B A
Agriculture Research Service, U.S. Department of Agriculture, Wyndmoor, PA 19038, USA.
Int J Food Microbiol. 2003 Sep 15;86(3):239-47. doi: 10.1016/s0168-1605(02)00550-0.
It has been shown that Clostridium perfringens isolates associated with food poisoning carry a chromosomal cpe gene, whereas nonfood-borne human gastrointestinal disease isolates carry a plasmid cpe gene. In addition, the chromosomal cpe gene isolates exhibit greater heat resistance as compared with the plasmid cpe strains. Therefore, the current study conducted ultrastructural measurements of spores from several plasmid and chromosomal cpe-positive C. perfringens isolates. In support of the dehydration mechanism of spore heat resistance, the C. perfringens spore core average size was found to show a negative correlation with D-values for spores obtained at 100 degrees C. Dipicolinic acid (DPA) concentrations assayed for the spores did not correlate well with C. perfringens spore core averages nor with D(10)-values at 100 degrees C. Spore core thickness might be a distinguishing phenotypic characteristic used to identify heat resistance and survival potential of C. perfringens in improperly cooked foods.
研究表明，与食物中毒相关的产气荚膜梭菌分离株携带染色体cpe基因，而非食源性人类胃肠道疾病分离株携带质粒cpe基因。此外，与质粒cpe菌株相比，染色体cpe基因分离株表现出更高的耐热性。因此，本研究对几种质粒和染色体cpe阳性产气荚膜梭菌分离株的孢子进行了超微结构测量。为支持孢子耐热性的脱水机制，发现产气荚膜梭菌孢子核心平均大小与在100℃下获得的孢子的D值呈负相关。对孢子检测的吡啶二羧酸（DPA）浓度与产气荚膜梭菌孢子核心平均值以及100℃下的D（10）值均无良好相关性。孢子核心厚度可能是用于识别产气荚膜梭菌在烹饪不当的食物中的耐热性和生存潜力的一个显著表型特征。
