Mechanism for transfer of transposon Tn2010 carrying macrolide resistance genes in Streptococcus pneumoniae and its effects on genome evolution
(0) Objectives: The objective of this study was to identify the mechanism responsible for the horizontal transfer of transposon Tn2010 in Streptococcus pneumoniae, and the genomic alterations introduced by the transfer process.Methods: Tn2010 was identified using PCR in 15 clinical isolates of S.pneumoniae with erythromycin resistance.S.pneumoniae and Enterococcus faecalis isolates were used as recipient cells in mating and transformation experiments to test the conjugative transferability and transformability of Tn2010.Whole-genome sequencing was used to assess the effects of the Tn2010 transfer on recipient genomes.The biological cost of the horizontal acquisition of Tn2010 and additional genomic changes was investigated by growth competition experiments.Results: Tn2010 was transformed at a frequency of 3 × 10-7 transformants per cfu, whereas no transconjugants were detected using S.pneumoniae or E.faecalis as recipient cells.Genome analysis showed that many other recombinations were scattered throughout the genome of the transformants in addition to transposon Tn2010.The transformants demonstrated a negligible fitness cost compared with the wild-type strain.Conclusions: Tn2010 tended to be transferred by transformation rather than conjugation in S.pneumoniae, and the spread of Tn2010 could have a profound effect on the evolution of the genome.The acquisition of Tn2010 with negligible fitness cost may facilitate spread of the transposon.
transformation recombination fitness cost
Wenqing Zhou Kaihu Yao Gang Zhang Yonghong Yang Yun Li Yuan Lv Jie Feng
State Key Laboratory or Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Key Laboratory of Major Diseases in Children and National Key Discipline of Pediatrics, Ministry of Institute of Clinical Pharmacology, Peking University First Hospital, Beijing,China State Key Laboratory or Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences,
国际会议
北京
英文
265-268
2018-03-29（万方平台首次上网日期，不代表论文的发表时间）