A Novel Anti-CRISPR AcrIE9.2 Is Associated with Dissemination of bla KPC Plasmids in Klebsiella pneumoniae Sequence Type 15

Sequence type (ST) 15 has become an emerging clone of carbapenem-resistant Klebsiella pneumoniae in which type I-E* CRISPR-Cas usually exists, indicating that the CRISPR-Cas system may not be able to block the transfer of bla KPC plasmids. The purpose of this study was to explore the mechanisms underlying dissemination of bla KPC plasmids in K. pneumoniae ST15.