Pcr And Rflp Analysis As Diagnostic Tests

聚合酶链式反应(PCR)扩增快速生长的分枝杆菌和诺卡氏菌的部分基因组，然后对扩增产物进行限制性片段长度多态性(RFLP)分析，已被证明是诊断实验室中一种有用的技术。与根据生化测试进行常规鉴定所需的一个月或更长时间相比，在生物隔离后的几天内就可以在物种一级对这些生物体进行鉴定。此外，与生化检测相比，这些分子程序可以更准确地区分物种和亚种。我们对诺卡氏菌基因组的两个不同区域(16S核糖体RNA基因的一部分和热休克蛋白基因的一部分)的研究表明，到目前为止还没有被识别的诺卡氏菌物种的存在；进一步表征这些生物的工作正在进行中。此外，我们还发现了一些诺卡氏菌是人类病原体，据我们所知，这些病原体在西半球以前没有报道过会导致患者患病，或者根本不知道是人类病原体。一份描述我们方法的手稿已经出版。我们目前正在撰写关于诺卡氏菌的一些发现，我们已经发现这种不寻常的诺卡氏菌是人类疾病的媒介。

Polymerase chain reaction (PCR) amplification of a portion of the genome of both rapidly growing Mycobacteria and Nocardia species, followed by restriction fragment length polymorphism (RFLP) analysis of the amplification products, has proven to be a useful technique in the diagnostic laboratory. Identification of these organisms at the species level can be obtained within a few days of organism isolation, as compared with the month or more required for conventional identification based on biochemical testing. In addition, these molecular procedures allow more accurate discrimination among species and subspecies than is possible with biochemical testing. Our work with two different areas of the Nocardia genome (a portion of the gene for 16S ribosomal RNA and a portion of the gene for the heat-shock protein) has suggested the existence of hitherto unrecognized Nocardia species; work is ongoing to characterize these organisms further. In addition, we have found some species of Nocardia to be human pathogens that were not previously reported to cause disease in patients in the western hemisphere, or were not known to be human pathogens at all, so far as we know. A manuscript describing our methodology has been published. We are currently writing up some of our findings on the unusual Nocardia species that we have found to be agents of disease in man.