Barbour A G, Maupin G O, Teltow G J, Carter C J, Piesman J
Department of Microbiology, University of Texas Health Science Center, San Antonio 78284, USA.
J Infect Dis. 1996 Feb;173(2):403-9. doi: 10.1093/infdis/173.2.403.
Bites from the hard tick Amblyomma americanum are associated with a Lyme disease-like illness in the southern United States. To identify possible etiologic agents for this disorder, A. americanum ticks were collected in Missouri, Texas, New Jersey, and New York and examined microscopically. Uncultivable spirochetes were present in approximately 2% of the ticks. Borrelia genus-specific oligonucleotides for the flagellin and 16S rRNA genes were used for amplification of DNA. Products were obtained from ticks containing spirochetes by microscopy but not from spirochete-negative ticks. Sequences of partial genes from spirochetes in Texas and New Jersey ticks differed by only 2 of 641 nucleotides for flagellin and 2 of 1336 nucleotides for 16S rRNA. Phylogenetic analysis showed that the spirochete was a Borrelia species distinct from previously characterized members of this genus, including Borrelia burgdorferi. Gene amplification could be used to detect these spirochetes in ticks and possible mammalian hosts.
美国南部，硬蜱美洲钝眼蜱叮咬会引发类似莱姆病的疾病。为确定该疾病可能的病原体，在密苏里州、得克萨斯州、新泽西州和纽约采集了美洲钝眼蜱，并进行显微镜检查。约2%的蜱中存在不可培养的螺旋体。利用针对鞭毛蛋白和16S rRNA基因的疏螺旋体属特异性寡核苷酸对DNA进行扩增。通过显微镜从含有螺旋体的蜱中获得了扩增产物，但未从螺旋体阴性的蜱中获得。得克萨斯州和新泽西州蜱中螺旋体部分基因的序列，鞭毛蛋白641个核苷酸中只有2个不同，16S rRNA的1336个核苷酸中也只有2个不同。系统发育分析表明，该螺旋体是一种疏螺旋体，与该属先前鉴定的成员不同，包括伯氏疏螺旋体。基因扩增可用于检测蜱及可能的哺乳动物宿主中的这些螺旋体。
