Jacobsen Louise, Wilcks Andrea, Hammer Karin, Huys Geert, Gevers Dirk, Andersen Sigrid Rita
Department of Microbiology and Risk Assessment, Danish Institute for Food and Veterinary Research, Søborg, Denmark.
FEMS Microbiol Ecol. 2007 Jan;59(1):158-66. doi: 10.1111/j.1574-6941.2006.00212.x. Epub 2006 Oct 2.
Two wild-type strains of Lactobacillus plantarum previously isolated from fermented dry sausages were analysed for their ability to transfer antibiotic resistance plasmids in the gastrointestinal tract. For this purpose, we used gnotobiotic rats as an in vivo model. Rats were initially inoculated with the recipient Enterococcus faecalis JH2-2 at a concentration of 10(10) CFU mL(-1). After a week, either of the two donors L. plantarum DG 522 (harbouring a tet(M)-containing plasmid of c. 40 kb) or L. plantarum DG 507 [harbouring a tet(M)-containing plasmid of c. 10 kb and an erm(B)-containing plasmid of c. 8.5 kb] was introduced at concentrations in the range of 10(8)-10(10) CFU mL(-1). Two days after donor introduction, the first transconjugants (TCs) were detected in faecal samples. The detected numbers of tet(M)-TCs were comparable for the two donors. In both cases, this number increased to c. 5 x 10(2) CFU g(-1) faeces towards the end of the experiment. For erm(B)-TCs, the number was significantly higher and increased to c. 10(3) CFU g(-1) faeces. To our knowledge, this is the first study showing in vivo transfer of wild-type antibiotic resistance plasmids from L. plantarum to E. faecalis.
对先前从发酵干香肠中分离出的两株植物乳杆菌野生型菌株在胃肠道中转移抗生素抗性质粒的能力进行了分析。为此，我们使用无菌大鼠作为体内模型。大鼠最初以10(10) CFU mL(-1) 的浓度接种受体粪肠球菌JH2-2。一周后，以10(8)-10(10) CFU mL(-1) 的浓度引入两株供体植物乳杆菌DG 522（携带一个约40 kb含tet(M) 的质粒）或植物乳杆菌DG 507 [携带一个约10 kb含tet(M) 的质粒和一个约8.5 kb含erm(B) 的质粒] 中的一株。引入供体两天后，在粪便样本中检测到第一批转接合子（TCs）。检测到的tet(M)-TCs数量在两种供体中相当。在两种情况下，该数量在实验结束时增加到约5 x 10(2) CFU g(-1) 粪便。对于erm(B)-TCs，数量明显更高，增加到约10(3) CFU g(-1) 粪便。据我们所知，这是第一项显示野生型抗生素抗性质粒从植物乳杆菌体内转移到粪肠球菌的研究。
