变形链球菌表面蛋白抗原A基因的DNA同源性

DNA homology of surface protein antigen A gene in mutans streptococci.

Abiko Y, Aoki H, Sato J, Koitabashi M, Takiguchi H

Department of Biochemistry, Nihon University School of Dentistry at Matsudo, Chiba, Japan.

Int J Biochem. 1989;21(9):1047-51. doi: 10.1016/0020-711x(89)90239-5.

Abstract

A recombinant plasmid, pYA724, containing an 8.45 kb DNA fragment encoding surface protein antigen A (spaA) from Streptococcus sobrinus 6715 was used to examine the DNA homology of the spaA gene with chromosomal DNA of various mutans streptococci strains. 2. Restriction endonuclease BamHI-digested pYA724 DNA was radio-labeled by nick-translation, and a DNA-DNA hybridization experiment was carried out. pYA724 DNA hybridized with chromosomal DNA of serotypes a, c, d, e, f and g strains, but not with b by dot DNA-hybridization and Southern blot DNA hybridization. 3. Chromosomal DNAs were isolated from several serotype c Streptococcus mutans strains, digested with BamHI, and analyzed by Southern blot DNA hybridization. pYA724 DNA hybridized with different sizes and numbers of BamHI-digested DNA fragments of the chromosomal DNAs. 4. These data indicated that all mutans streptococci strains except serotype b have DNA homologous with the spaA gene, although within the same serotype strain the spaA gene has a diversity of arrangement within the chromosome.

摘要

一个重组质粒pYA724，含有来自远缘链球菌6715编码表面蛋白抗原A（spaA）的8.45 kb DNA片段，用于检测spaA基因与各种变形链球菌菌株染色体DNA的DNA同源性。2. 用限制性内切酶BamHI消化的pYA724 DNA通过缺口平移进行放射性标记，并进行DNA-DNA杂交实验。通过点DNA杂交和Southern印迹DNA杂交，pYA724 DNA与血清型a、c、d、e、f和g菌株的染色体DNA杂交，但不与b杂交。3. 从几种血清型c变形链球菌菌株中分离染色体DNA，用BamHI消化，并通过Southern印迹DNA杂交进行分析。pYA724 DNA与染色体DNA经BamHI消化的不同大小和数量的DNA片段杂交。4. 这些数据表明，除血清型b外，所有变形链球菌菌株都有与spaA基因同源的DNA，尽管在同一血清型菌株内，spaA基因在染色体内的排列具有多样性。