Transposase-Mediated Excision, Conjugative Transfer, and Diversity of ICE 6013 Elements in Staphylococcus aureus

作者：Emily A. Sansevere, Xiao Luo, Joo Youn Park, Sunghyun Yoon, Keun Seok Seo, D. Ashley Robinson · 发表于：Journal of Bacteriology · 年份：2017 · DOI：10.1128/jb.00629-16 · 被引用次数：20 · 研究领域：Antimicrobial Resistance in Staphylococcus、Bacteriophages and microbial interactions、Bacterial Genetics and Biotechnology

ABSTRACT ICE 6013 represents one of two families of integrative conjugative elements (ICEs) identified in the pan-genome of the human and animal pathogen Staphylococcus aureus . Here we investigated the excision and conjugation functions of ICE 6013 and further characterized the diversity of this element. ICE 6013 excision was not significantly affected by growth, temperature, pH, or UV exposure and did not depend on recA . The IS 30 -like DDE transposase (Tpase; encoded by orf1 and orf2 ) of ICE 6013 must be uninterrupted for excision to occur, whereas disrupting three of the other open reading frames (ORFs) on the element significantly affects the level of excision. We demonstrate that ICE 6013 conjugatively transfers to different S. aureus backgrounds at frequencies approaching that of the conjugative plasmid pGO1. We found that excision is required for conjugation, that not all S. aureus backgrounds are successful recipients, and that transconjugants acquire the ability to transfer ICE 6013 . Sequencing of chromosomal integration sites in serially passaged transconjugants revealed a significant integration site preference for a 15-bp AT-rich palindromic consensus sequence, which surrounds the 3-bp target site that is duplicated upon integration. A sequence analysis of ICE 6013 from different host strains of S. aureus and from eight other species of staphylococci identified seven divergent subfamilies of ICE 6013 that include sequences previously classified as a transposon...