Dmitriev A, Suvorov A, Totolian A
Institute of Experimental Medicine, Academy of the Medical Sciences, St. Petersburg, Russia.
FEMS Microbiol Lett. 1998 Oct 1;167(1):33-9. doi: 10.1111/j.1574-6968.1998.tb13204.x.
A detailed analysis of two Streptococcus agalactiae (group B streptococcus, GBS) strains was performed by pulsed field gel electrophoresis (PFGE). Digestion of the chromosomal DNA with SmaI and SgrAI endonucleases, followed by separation and analysis of fragments by PFGE was carried out. Physical chromosomal maps of serotype II/(alpha + beta) and III/alpha strains of S. agalactiae were constructed. The GBS genome size was estimated to be 2200 kb. Sixteen GBS genes were used as probes and were located on the restriction maps of both strains by DNA-DNA hybridization. Six copies of ribosomal operons were found in the genome of the analyzed strains. Significant differences in the restriction patterns of chromosomal DNA and DNA-DNA hybridization between the two analyzed strains were detected so that DNA restriction patterns may be used to trace outbreaks of disease. The overall GBS chromosomal organization as determined is fairly conserved.
采用脉冲场凝胶电泳（PFGE）对两株无乳链球菌（B组链球菌，GBS）进行了详细分析。用SmaI和SgrAI核酸内切酶消化染色体DNA，然后通过PFGE分离和分析片段。构建了无乳链球菌血清型II/（α+β）和III/α菌株的物理染色体图谱。估计GBS基因组大小为2200 kb。使用16个GBS基因作为探针，通过DNA-DNA杂交将其定位在两株菌株的限制性图谱上。在所分析菌株的基因组中发现了六个核糖体操纵子拷贝。检测到两株分析菌株之间染色体DNA的限制性图谱和DNA-DNA杂交存在显著差异，因此DNA限制性图谱可用于追踪疾病暴发。所确定的GBS染色体总体组织相当保守。
