Vossbrinck C R, Baker M D, Didier E S, Debrunner-Vossbrinck B A, Shadduck J A
Office of Agricultural Entomology, Urbana, Illinois 61801.
J Eukaryot Microbiol. 1993 May-Jun;40(3):354-62. doi: 10.1111/j.1550-7408.1993.tb04928.x.
A segment of ribosomal DNA, about 1,350 base pairs long, was amplified from the microsporidian species Encephalitozoon hellem, isolated from AIDS patients, and Encephalitozoon cuniculi. The amplified DNA segment extends from position 530 in the small ribosomal RNA subunit to position 580 in the large ribosomal RNA subunit. A comparison of sequence data from this region for Encephalitozoon hellem and Encephalitozoon cuniculi shows relatively high sequence similarity, supporting the placement of these two organisms in the same genus. At the same time, sequence differences between the two organisms confirm that they are not the same species. Three separate isolates of E. hellem were sequenced in the highly variable intervening spacer region. The sequence was identical for all three isolates. Within the amplified DNA segment, regions were sequenced which yield highly variable, moderately variable and highly conserved sequence information, appropriate for comparison with other species in the phylum Microspora at all taxonomic levels. We suggest that sequence data from these regions be included in future species descriptions for the purposes of species identification and phylogenetic analysis. Restriction digests of the amplified region are presented and give a rapid method for distinguishing between the two Encephalitozoon species.
从艾滋病患者体内分离出的微孢子虫物种海伦脑炎微孢子虫（Encephalitozoon hellem）和兔脑炎微孢子虫（Encephalitozoon cuniculi）中扩增出一段约1350个碱基对长的核糖体DNA片段。扩增出的DNA片段从小核糖体RNA亚基的第530位延伸到大核糖体RNA亚基的第580位。对海伦脑炎微孢子虫和兔脑炎微孢子虫该区域序列数据的比较显示出相对较高的序列相似性，支持将这两种生物归为同一属。同时，两种生物之间的序列差异证实它们不是同一物种。对三个独立的海伦脑炎微孢子虫分离株在高度可变的间隔区进行了测序。所有三个分离株的序列相同。在扩增出的DNA片段内，对一些区域进行了测序，这些区域产生了高度可变、中度可变和高度保守的序列信息，适用于在所有分类水平上与微孢子虫门中的其他物种进行比较。我们建议将这些区域的序列数据纳入未来的物种描述中，用于物种鉴定和系统发育分析。给出了扩增区域的限制性酶切分析，提供了一种快速区分这两种脑炎微孢子虫物种的方法。
