Department of Medical Microbiology and Immunology, School of Medicine, University of California, Davis, CA, 95616, USA,
Mycopathologia. 2015 Jun;179(5-6):373-9. doi: 10.1007/s11046-014-9857-y. Epub 2015 Jan 11.
Fifteen Coccidioides isolates were previously examined for genetic diversity using restriction fragment length polymorphism (RFLP); two fragment patterns were observed. Two isolates demonstrated one banding pattern (designated RFLP group I), while the remaining 13 isolates demonstrated a second pattern (designated RFLP group II). Recently, molecular studies supported the division of the genera Coccidioides into two species: Coccidioides posadasii and Coccidioides immitis. It has been assumed that the species division corresponds to the RFLP grouping. We tested this hypothesis by amplifying the ribosomal DNA internal transcribed spacer region as well as the dioxygenase, serine proteinase, and urease genes from 13 isolates previously examined by RFLP and then sequencing the PCR products. The appropriate species for each isolate was assigned using phylogenetically informative sites. The RFLP grouping agreed with the Coccidioides species assignment for all but one isolate, which may represent a hybrid. In addition, polymorphic sites among the four genes examined were in agreement for species assignment such that analysis of a single gene may be sufficient for species assignment.
十五株荚膜组织胞浆菌分离株先前曾用限制片段长度多态性（RFLP）检测遗传多样性；观察到两种片段模式。两种分离株显示一种带型（指定为 RFLP 组 I），而其余 13 株分离株显示第二种模式（指定为 RFLP 组 II）。最近，分子研究支持荚膜组织胞浆菌属分为两个种：荚膜组织胞浆菌和荚膜组织胞浆菌。人们认为种的划分与 RFLP 分组相对应。我们通过扩增核糖体 DNA 内部转录间隔区以及先前用 RFLP 检测的 13 株分离株的加双氧酶、丝氨酸蛋白酶和脲酶基因，然后对 PCR 产物进行测序，检验了这一假设。使用具有系统发育信息的位点为每个分离株指定适当的物种。除了一个分离株外，RFLP 分组与荚膜组织胞浆菌种的归属一致，该分离株可能代表杂种。此外，在四个基因中检查到的多态性位点在种的归属上是一致的，因此分析单个基因可能足以确定种的归属。
