Orsburn Benjamin, Melville Stephen B, Popham David L
Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA.
Appl Environ Microbiol. 2008 Jun;74(11):3328-35. doi: 10.1128/AEM.02629-07. Epub 2008 Mar 31.
The endospores formed by strains of type A Clostridium perfringens that produce the C. perfringens enterotoxin (CPE) are known to be more resistant to heat and cold than strains that do not produce this toxin. The high heat resistance of these spores allows them to survive the cooking process, leading to a large number of food-poisoning cases each year. The relative importance of factors contributing to the establishment of heat resistance in this species is currently unknown. The present study examines the spores formed by both CPE(+) and CPE(-) strains for factors known to affect heat resistance in other species. We have found that the concentrations of DPA and metal ions, the size of the spore core, and the protoplast-to-sporoplast ratio are determining factors affecting heat resistance in these strains. While the overall thickness of the spore peptidoglycan was found to be consistent in all strains, the relative amounts of cortex and germ cell wall peptidoglycan also appear to play a role in the heat resistance of these strains.
已知产生产气荚膜梭菌肠毒素（CPE）的A型产气荚膜梭菌菌株形成的芽孢比不产生该毒素的菌株对热和冷更具抵抗力。这些芽孢的高耐热性使它们能够在烹饪过程中存活下来，每年导致大量食物中毒事件。目前尚不清楚该物种中导致耐热性形成的因素的相对重要性。本研究检查了CPE（+）和CPE（-）菌株形成的芽孢中已知影响其他物种耐热性的因素。我们发现二吡啶二酸（DPA）和金属离子的浓度、芽孢核心的大小以及原生质体与芽孢体的比例是影响这些菌株耐热性的决定性因素。虽然发现所有菌株中芽孢肽聚糖的总厚度是一致的，但皮层和生殖细胞壁肽聚糖的相对含量似乎也在这些菌株的耐热性中起作用。
