Bourgoin F, Guédon G, Gintz B, Decaris B
UA INRA952, Université Henri Poincaré-Nancy I, Vandoeuvre-lès-Nancy, 54506, France.
Plasmid. 1998 Jul;40(1):44-9. doi: 10.1006/plas.1998.1337.
A novel insertion sequence, IS1194, has been identified in the lactic acid bacterium Streptococcus thermophilus CNRZ368. This 1200-bp element has 16-bp imperfect terminal inverted repeats. The single large open reading frame of this element encodes a 332-amino-acid protein that displays similarities with transposases encoded by bacterial insertion sequences belonging to the IS5 group of the IS4 family. A single copy of IS1194 was detected by hybridization in only 2 of the 19 S. thermophilus strains tested and in 4 of the 13 Lactococcus lactis strains investigated. This suggests that this IS element was acquired by horizontal transfer. The unique IS1194 copy of S. thermophilus CNRZ368 is located in a region of at least 12 kb that was probably acquired by horizontal transfer from L. lactis. Furthermore, the IS1194 right end is identical to sequences found in a broad-host-range conjugative plasmid from Streptococcus pyogenes, pSM19035.
在嗜热链球菌CNRZ368中鉴定出一种新的插入序列IS1194。这个1200碱基对的元件具有16个碱基对的不完全末端反向重复序列。该元件的单一大型开放阅读框编码一个332个氨基酸的蛋白质，该蛋白质与属于IS4家族IS5组的细菌插入序列所编码的转座酶具有相似性。通过杂交检测发现，在测试的19株嗜热链球菌菌株中只有2株含有单拷贝的IS1194，在调查的13株乳酸乳球菌菌株中有4株含有。这表明该插入序列是通过水平转移获得的。嗜热链球菌CNRZ368中独特的IS1194拷贝位于至少12 kb的区域，该区域可能是从乳酸乳球菌通过水平转移获得的。此外，IS1194的右端与化脓性链球菌的一个广宿主范围接合质粒pSM19035中的序列相同。
