Frank C, Steiner K, Malke H
Institute for Molecular Biology, Jena University, Germany.
Med Microbiol Immunol. 1995 Oct;184(3):139-46. doi: 10.1007/BF00224351.
Using ten gene-specific probes from the cloned and sequenced streptokinase gene (skc) region (8,931 bp) of Streptococcus equisimilis H46A, a human serogroup C strain, the conservation of these genes and their linkage relationships were studied by Southern hybridization in pathogenic streptococci differing taxonomically, serologically, in regard to their host range, and in the class of plasminogen activator produced. The results indicate that in S. pyogenes (strains A374, NZ131 and SF130/13) and a human group G strain (G19,908) both gene content and gene order as determined for H46A (dexB-abc-lrp-skc-orfl-rel) are preserved. The same is true of an equine S. equisimilis isolate (87-542-W), the streptokinase gene of which has been shown to hybridize detectably with skc, a result at variance with that obtained previously by others. In contrast, the chromosomal DNA of three S. uberis strains (0140J, C198, C216) of bovine origin, two of which produced a plasminogen activator different from streptokinase, hybridized only with dexB-, abc- and rel-specific probes, and the homologues of these genes appeared to lie close to each other. The maintenance of the organization of the streptokinase gene region in strains differing in overall chromosomal character suggests that this gene arrangement is of selective advantage.
使用来自人C群菌株马链球菌兽疫亚种H46A克隆并测序的链激酶基因（skc）区域（8,931 bp）的10个基因特异性探针，通过Southern杂交研究了这些基因在分类学、血清学、宿主范围以及所产生的纤溶酶原激活剂类别方面存在差异的致病性链球菌中的保守性及其连锁关系。结果表明，化脓性链球菌（菌株A374、NZ131和SF130/13）和人G群菌株（G19,908）中，如H46A所确定的基因含量和基因顺序（dexB-abc-lrp-skc-orfl-rel）均得以保留。一匹马的马链球菌分离株（87-542-W）也是如此，其链激酶基因已被证明可与skc发生可检测到的杂交，这一结果与其他人先前获得的结果不同。相比之下，三株牛源乳房链球菌菌株（0140J、C198、C216）的染色体DNA，其中两株产生的纤溶酶原激活剂不同于链激酶，仅与dexB-、abc-和rel特异性探针杂交，并且这些基因的同源物似乎彼此相邻。在整体染色体特征不同的菌株中链激酶基因区域的组织得以维持，这表明这种基因排列具有选择优势。
