Caudry S, Klitorinos A, Gharbia S E, Pssara N, Siboo R, Keng T, Chan E C
Department of Oral Biology, Faculty of Dentistry, McGill University, Quebec, Canada.
Oral Microbiol Immunol. 1995 Feb;10(1):8-12. doi: 10.1111/j.1399-302x.1995.tb00111.x.
Fifteen oral spirochete strains belonging to the species Treponema denticola, Treponema vencentii and Treponema socranskii as well as 9 fresh clinical isolates were screened for the presence of extrachromosomal plasmid DNA by a modified alkaline lysis procedure. A 2.6-kb plasmid was detected in both T. denticola ATCC 33520 and T. denticola e'. The 2.6-kb plasmid from T. denticola e' was shown to be similar to pTD1, previously reported by Ivic et al. in T. denticola ATCC 33520 on the basis of molecular weight, restriction endonuclease profile and DNA:DNA hybridization. T. denticola ATCC 33520 and T. denticola e' share 65% DNA homology and belong to different serological groups. This dissimilarity has been reconfirmed by specific immunofluorescence using polyclonal and monoclonal antibodies. A plasmid-free T. denticola ATCC 33520 was identified. Comparative studies have shown no antigenic, morphological, or genetic differences between the plasmid-bearing and the plasmid-free strain. In addition, screening of fresh clinical isolates of spirochetes revealed the presence of a 4.2-kb plasmid in 4 of these strains.
采用改良的碱裂解法，对15株属于齿垢密螺旋体、文森特密螺旋体和索氏密螺旋体的口腔螺旋体菌株以及9株新鲜临床分离株进行了染色体外质粒DNA存在情况的筛选。在齿垢密螺旋体ATCC 33520和齿垢密螺旋体e'中均检测到一个2.6 kb的质粒。基于分子量、限制性内切酶图谱和DNA:DNA杂交分析，齿垢密螺旋体e'的2.6 kb质粒与Ivic等人先前在齿垢密螺旋体ATCC 33520中报道的pTD1相似。齿垢密螺旋体ATCC 33520和齿垢密螺旋体e'的DNA同源性为65%，且属于不同的血清学组。使用多克隆和单克隆抗体进行的特异性免疫荧光分析再次证实了这种差异。鉴定出一株无质粒的齿垢密螺旋体ATCC 33520。比较研究表明，有质粒菌株和无质粒菌株之间在抗原性、形态学或遗传学方面均无差异。此外，对螺旋体新鲜临床分离株的筛选显示，其中4株存在一个4.2 kb的质粒。
