Schauer D B, Zabel B A, Pedraza I F, O'Hara C M, Steigerwalt A G, Brenner D J
Division of Toxicology, Massachusetts Institute of Technology, Cambridge 02139, USA.
J Clin Microbiol. 1995 Aug;33(8):2064-8. doi: 10.1128/jcm.33.8.2064-2068.1995.
An unusual bacterial pathogen of laboratory mice has been previously classified as an atypical biotype of Citrobacter freundii. Designated C. freundii biotype 4280, this bacterium is the etiologic agent of transmissible murine clonic hyperplasia. An eaeA gene has been shown to be present in this organism and to be necessary for virulence in laboratory mice. However, other biotypes of C. freundii lack DNA homology with the eaeA gene. Because of the recent reclassification in which five named species and three unnamed species, all previously considered C. freundii, were described, we determined the taxonomic status of C. freundii biotype 4280. With a battery of biochemical tests and DNA relatedness studies, three isolates of C. freundii biotype 4280 were shown to be members of an unnamed Citrobacter species, designated species 9. In total, six isolates of Citrobacter species 9, but none of the type strains of the other eight named species or of the two remaining unnamed species of Citrobacter, were shown to possess DNA homology with both the eaeA and the eaeB genes. Species 9 was named Citrobacter rodentium sp. nov.
一种不同寻常的实验小鼠细菌病原体先前被归类为弗氏柠檬酸杆菌的非典型生物型。这种细菌被命名为弗氏柠檬酸杆菌生物型4280,是可传播性小鼠克隆性增生的病原体。已证明eaeA基因存在于该生物体中,并且是实验小鼠致病力所必需的。然而,弗氏柠檬酸杆菌的其他生物型与eaeA基因缺乏DNA同源性。由于最近的重新分类,描述了五个命名物种和三个未命名物种,所有这些先前都被认为是弗氏柠檬酸杆菌,我们确定了弗氏柠檬酸杆菌生物型4280的分类地位。通过一系列生化试验和DNA相关性研究,弗氏柠檬酸杆菌生物型4280的三个分离株被证明是一个未命名的柠檬酸杆菌物种(命名为物种9)的成员。总共,柠檬酸杆菌物种9的六个分离株,但其他八个命名物种的模式菌株或柠檬酸杆菌的另外两个未命名物种的模式菌株均未显示与eaeA和eaeB基因具有DNA同源性。物种9被命名为啮齿柠檬酸杆菌新种。