Blomqvist G, Wesslén L, Påhlson C, Hjelm E, Pettersson B, Nikkilä T, Allard U, Svensson O, Uhlén M, Morein B, Friman G
Department of Virology, National Veterinary Institute, Uppsala, Sweden.
J Clin Microbiol. 1997 Aug;35(8):1988-95. doi: 10.1128/jcm.35.8.1988-1995.1997.
An alpha-2 proteobacterium, previously unknown as determined by its phylogenetic characteristics and the DNA sequence of its 16S rRNA gene, was isolated from a patient who presented an unusual clinical picture, including high remitting fever and multiorgan involvement. The bacterium was detected in multiple plasma samples, obtained during the acute phase of the disease, after cocultivation in cell culture media. Electron microscopy of the organism showed a three-layer laminar cell wall and electron-dense granules within the cytoplasm, as well as a polar flagellum. By means of PCR followed by sequencing of amplified 16S ribosomal DNA fragments, the bacterium was found to differ from all species for which ribosomal sequence information is available. It is here provisionally named the Rasbo bacterium. At a subsequent relapse, the bacterium was identified in pericardial fluid both by PCR/sequencing and by direct electron microscopy. At a second relapse, it was again cultured from plasma. After in vitro adaptation to solid media, the MICs of various antibiotics could be determined. A transient immunoglobulin M (IgM) but no IgG response to the bacterium was found by an indirect immunofluorescence test, as well as by an immobilization test during the acute phase of the disease.
从一名出现异常临床表现（包括高热反复和多器官受累）的患者身上分离出一种α-2变形杆菌，根据其系统发育特征和16S rRNA基因的DNA序列，此前该菌并不为人所知。在疾病急性期采集的多个血浆样本中，经细胞培养基共培养后检测到了这种细菌。对该微生物进行电子显微镜检查发现其具有三层层状细胞壁，细胞质内有电子致密颗粒，还有一根极鞭毛。通过聚合酶链反应（PCR），随后对扩增的16S核糖体DNA片段进行测序，发现该细菌与所有已知核糖体序列信息的物种都不同。在此暂将其命名为拉斯博菌。在随后的复发期，通过PCR/测序和直接电子显微镜检查在心包液中均鉴定出了该细菌。在第二次复发时，又从血浆中培养出了该细菌。经体外适应固体培养基后，可测定各种抗生素的最低抑菌浓度（MIC）。在疾病急性期，通过间接免疫荧光试验以及固定试验发现，患者对该细菌产生了短暂的免疫球蛋白M（IgM）反应，但未产生IgG反应。
