Shoemaker N B, Getty C, Gardner J F, Salyers A A
J Bacteriol. 1986 Mar;165(3):929-36. doi: 10.1128/jb.165.3.929-936.1986.
The gene for resistance to erythromycin and clindamycin, which is carried on the conjugative Bacteroides plasmid, pBF4, has been shown previously to be part of an element (Tn4351) that transposes in Escherichia coli. We have now introduced Tn4351 into Bacteroides uniformis 0061 on the following two suicide vectors: (i) the broad-host-range IncP plasmid R751 (R751::Tn4351) and (ii) pSS-2, a chimeric plasmid which contains 33 kilobases of pBF4 (including Tn4351) cloned into the IncQ plasmid RSF1010 and which is mobilized by R751. When E. coli HB101, carrying either R751::Tn4351 or R751 and pSS-2, was mated with B. uniformis under aerobic conditions, Emr transconjugants were detected at a frequency of 10(-6) to 10(-5) (R751::Tn4351) or 10(-8) to 10(-6) (R751 and pSS-2). In matings involving pSS-2, all Emr transconjugants contained simple insertions of Tn4351 in the chromosome, whereas in matings involving R751::Tn4351, about half of the Emr transconjugants had R751 cointegrated with Tn4351 in the chromosome. Of the Emr transconjugants, 13% were auxotrophs. Bacteroides spp. which had R751 cointegrated with Tn4351 in the chromosome did not transfer R751 or Tn4351 to E. coli HB101 or to isogenic B. uniformis, nor did the intergrated R751 mobilize pE5-2, an E. coli-Bacteroides shuttle vector that contains a transfer origin that is recognized by R751.
先前已证明，携带在接合性拟杆菌属质粒pBF4上的对红霉素和克林霉素的抗性基因是一种元件（Tn4351）的一部分，该元件可在大肠杆菌中发生转座。我们现在已将Tn4351导入以下两种自杀载体上的均匀拟杆菌0061中：（i）广宿主范围的IncP质粒R751（R751::Tn4351）和（ii）pSS-2，一种嵌合质粒，其包含克隆到IncQ质粒RSF1010中的33千碱基的pBF4（包括Tn4351），并且由R751进行转移。当携带R751::Tn4351或R751和pSS-2的大肠杆菌HB101在需氧条件下与均匀拟杆菌交配时，以10^(-6)至10^(-5)（R751::Tn4351）或10^(-8)至10^(-6)（R751和pSS-2）的频率检测到红霉素抗性转接合子。在涉及pSS-2的交配中，所有红霉素抗性转接合子在染色体中都含有Tn4351的简单插入，而在涉及R751::Tn4351的交配中，约一半的红霉素抗性转接合子在染色体中有与Tn4351共整合的R751。在红霉素抗性转接合子中，13%是营养缺陷型。染色体中具有与Tn4351共整合的R751的拟杆菌属细菌不会将R751或Tn4351转移至大肠杆菌HB101或同基因的均匀拟杆菌，整合的R751也不会转移pE5-2，一种大肠杆菌-拟杆菌穿梭载体，其包含一个被R751识别的转移起始位点。
