Gordillo M E, Singh K V, Murray B E
Department of Internal Medicine, University of Texas Medical School, Houston 77030.
J Clin Microbiol. 1993 Jun;31(6):1570-4. doi: 10.1128/jcm.31.6.1570-1574.1993.
Hybridization of EcoRI- and HindIII-digested chromosomal DNAs from 41 isolates of Enterococcus faecalis with probes for rRNA genes was performed (ribotyping). The ability of ribotyping to distinguish strains at the subspecies level was compared with results previously determined by pulsed-field gel electrophoresis (PFGE). With EcoRI, seven ribopatterns (usually differing by only one band) were found, while PFGE had previously shown 25 clearly different patterns plus six related variants. Digestion with HindIII generated a few additional patterns but still failed to differentiate some strains that had very different PFGE patterns. Ribotyping with BscI has also been reported to be inadequate for subspecies strain differentiation (L. M. Hall, B. Duke, M. Guiney, and R. Williams, J. Clin. Microbiol. 30:915-919, 1992). Although ribotyping with other restriction endonucleases may perform better in distinguishing different strains, at present PFGE appears to be superior for strain differentiation.
用rRNA基因探针与41株粪肠球菌经EcoRI和HindIII酶切的染色体DNA进行杂交（核糖体分型）。将核糖体分型在亚种水平区分菌株的能力与先前通过脉冲场凝胶电泳（PFGE）确定的结果进行比较。用EcoRI酶切时，发现了7种核糖体图谱（通常仅相差一条带），而PFGE先前显示有25种明显不同的图谱以及6种相关变体。用HindIII酶切产生了一些额外的图谱，但仍无法区分一些PFGE图谱差异很大的菌株。据报道，用BscI进行核糖体分型也不足以区分亚种菌株（L.M.霍尔、B.杜克、M.吉尼和R.威廉姆斯，《临床微生物学杂志》30:915 - 919，1992年）。尽管用其他限制性内切酶进行核糖体分型在区分不同菌株方面可能表现更好，但目前PFGE在菌株区分方面似乎更具优势。
