McOrist S, Gebhart C J, Boid R, Barns S M
Department of Veterinary Pathology, University of Edinburgh, Easter Bush, Midlothian, United Kingdom.
Int J Syst Bacteriol. 1995 Oct;45(4):820-5. doi: 10.1099/00207713-45-4-820.
A novel obligately intracellular bacterium, ileal symbiont intracellularis, which was obtained from the intestines of pigs with proliferative enteropathy disease, was grown in pure cocultures with tissue cultures of rat cells. An examination of the 16S ribosomal DNA gene sequence revealed that the isolates which we obtained are members of the delta subdivision of the Proteobacteria and that the sequences of these organisms exhibit a level of similarly of 91% with the sequence of Desulfovibrio desulfuricans ATCC 27774. These isolates were homogeneous and differed in cellular morphology, acid fastness, phenotype, electrophoretic protein profile, and habitat from Desulfovibrio species. On the basis of the results of an integrated study of the phenotype and genotype of a consistent morphological entity found in particular porcine cells and associated with a well-defined clinical condition, we concluded that these bacteria belong to a previously undescribed genus and species, for which we propose the name Lawsonia intracellularis gen. nov., sp. nov. A species-specific recombinant DNA probe was cloned previously, and this probe was used to identify the bacterium in tissue culture cells and in the ileal epithelia of pigs with proliferative enteropathy disease. Coculture of the organism with a rat enterocyte cell line allowed us to designate strain NCTC 12656 the type strain and to describe the new genus and species. The organism which we cultured is pathogenic for pigs and causes proliferative enteropathy lesions in their ilea and colons, and Koch's postulates were fulfilled for this organism.
一种新型专性细胞内细菌——回肠共生胞内菌，从患有增生性肠炎疾病的猪肠道中分离得到，它与大鼠细胞的组织培养物在纯共培养体系中生长。对16S核糖体DNA基因序列的检测显示，我们获得的分离株属于变形菌门δ亚纲，并且这些微生物的序列与脱硫脱硫弧菌ATCC 27774的序列有91%的相似性。这些分离株具有均一性，在细胞形态、抗酸性、表型、电泳蛋白图谱和栖息地方面与脱硫弧菌属不同。基于对在特定猪细胞中发现的、与明确临床病症相关的一致形态实体的表型和基因型的综合研究结果，我们得出结论，这些细菌属于一个此前未描述的属和种，我们为此提议命名为胞内劳森菌属（Lawsonia intracellularis），新属，新种。此前已克隆出一种物种特异性重组DNA探针，该探针用于在组织培养细胞和患有增生性肠炎疾病的猪回肠上皮中鉴定该细菌。该微生物与大鼠肠上皮细胞系的共培养使我们能够指定NCTC 12656菌株为模式菌株，并描述这个新属和新种。我们培养的这种微生物对猪具有致病性，可在猪的回肠和结肠中引起增生性肠炎病变，并且该微生物满足科赫法则。
