Asakura Hiroshi, Panutdaporn Nantika, Kawamoto Keiko, Igimi Shizunobu, Yamamoto Shigeki, Makino Sou-Ichi
Division of Biomedical Food Research, National Institute of Health Sciences, Tokyo, Japan.
Microbiol Immunol. 2007;51(9):875-81. doi: 10.1111/j.1348-0421.2007.tb03969.x.
Enterohemorrhagic Escherichia coli (EHEC) O157 strain F2, a food isolate of an outbreak, is resistant to oxidative stress, but has increased stress-sensitivity after passage through mice. The stress-sensitive variant of F2 (designated MP37) has decreased culturability, but retains membrane integrity under stress conditions, indicating that the cells enter a viable but non-culturable (VBNC) state. Proteomic analyses revealed that MP37 in the VBNC state had decreased levels of some oxidation-responsive factors (AhpCF, AceF), but it markedly increased levels of outer membrane protein W (OmpW). Because F2 expressed higher levels of some ribosome-associated proteins (RaiA, S6, Bcp) than MP37, the effect of animal passage on the induction of the VBNC state in the EHEC O157 cells might be due to ribosomal activity.
肠出血性大肠杆菌（EHEC）O157菌株F2是一次食源性暴发的分离株，它对氧化应激具有抗性，但在通过小鼠传代后应激敏感性增加。F2的应激敏感变体（命名为MP37）可培养性降低，但在应激条件下仍保持膜完整性，这表明细胞进入了活的但不可培养（VBNC）状态。蛋白质组学分析显示，处于VBNC状态的MP37中一些氧化反应因子（AhpCF、AceF）的水平降低，但外膜蛋白W（OmpW）的水平显著增加。由于F2表达的一些核糖体相关蛋白（RaiA、S6、Bcp）水平高于MP37，动物传代对EHEC O157细胞中VBNC状态诱导的影响可能归因于核糖体活性。
