空肠弯曲菌菌株产生的两种细胞毒素的检测与特性分析

Detection and characterization of two cytotoxins produced by Campylobacter jejuni strains.

作者信息

Hänel I, Schulze F, Hotzel H, Schubert E

机构信息

Federal Institute for Health Protection of Consumers and Veterinary Medicine, Division 4: Bacterial Animal Diseases and Zoonoses Control, Jena, Germany.

出版信息

Zentralbl Bakteriol. 1998 Jul;288(1):131-43. doi: 10.1016/s0934-8840(98)80111-4.

DOI:10.1016/s0934-8840(98)80111-4

PMID:9728413

Abstract

Campylobacter jejuni strains are able to produce at least two different cytotoxins called "cytolethal distending toxin" (CLDT) and "cytolethal rounding toxin" (CLRT). In this study, we investigated the corresponding changes in CHO-K1 cells using the cell counter and analyzer system CASY 1. Determination of the cell volume after toxin treatment of the cells is a useful criterion for differentiation between the cytotoxic activities produced by Campylobacter strains. Incubation of the cells with crude CLDT resulted in a decrease in the cell count combined with a dramatic increase of the mean cell volume in comparison to the control culture. A decrease in the cell count was also seen as a response to CLRT preparations, while this toxin had no effect on the mean cell volume determined. It was shown that only CLDT caused histone-associated DNA fragments in the cytoplasm of CHO-K1 cells indicating an apoptotic pathway of cell death. In addition, the polymerase chain reaction (PCR) was employed to screen Campylobacter strains for the presence of the cdtB gene sequence, which was detectable in all strains investigated.

摘要

空肠弯曲菌菌株能够产生至少两种不同的细胞毒素，分别称为“细胞致死性扩张毒素”（CLDT）和“细胞致死性圆化毒素”（CLRT）。在本研究中，我们使用细胞计数和分析仪系统CASY 1研究了CHO-K1细胞中的相应变化。测定毒素处理后细胞的体积是区分弯曲菌菌株产生的细胞毒性活性的有用标准。与对照培养相比，用粗制CLDT孵育细胞导致细胞计数减少，同时平均细胞体积急剧增加。细胞计数减少也被视为对CLRT制剂的反应，而这种毒素对测定的平均细胞体积没有影响。结果表明，只有CLDT会在CHO-K1细胞的细胞质中引起组蛋白相关的DNA片段，表明细胞死亡的凋亡途径。此外，采用聚合酶链反应（PCR）筛选弯曲菌菌株中cdtB基因序列的存在情况，在所研究的所有菌株中均可检测到该序列。