Whole Genome Characterization of the High-Risk Clone ST383 Klebsiella pneumoniae with a Simultaneous Carriage of blaCTX-M-14 on IncL/M Plasmid and blaCTX-M-15 on Convergent IncHI1B/IncFIB Plasmid from Egypt

Recently, Egypt has witnessed the emergence of multidrug-resistant (MDR) Klebsiella pneumoniae, which has posed a serious healthcare challenge. The accelerated dissemination of bla_CTX-M genes among these MDR K. pneumoniae, particularly bla_CTX-M-14 and bla_CTX-M-15, have been noted. In this study, we investigated the occurrence of bla_CTX-M-IV among K. pneumoniae recovered from the laboratory of a major hospital in Alexandria. The 23 tested isolates showed an MDR phenotype and the bla_CTX-M-IV gene was detected in ≈22% of the isolates. The transformation of plasmids harboring bla_CTX-M-IV to chemically competent cells of Escherichia coli DH5α was successful in three out of five of the tested bla_CTX-M-IV-positive isolates. Whole genome sequencing of K22 indicated that the isolate belonged to the high-risk clone ST383, showing a simultaneous carriage of bla_CTX-M-14 on IncL/M plasmid, i.e., pEGY22_CTX-M-14, and bla_CTX-M-15 on a hybrid IncHI1B/IncFIB plasmid, pEGY22_CTX-M-15. Alignment of both plasmids revealed high similarity with those originating in the UK, Germany, Australia, Russia, China, Saudi Arabia, and Morocco. pEGY22_CTX-M-15 was a mosaic plasmid that demonstrated convergence of MDR and virulence genes. The emergence of such a plasmid with enhanced genetic plasticity constitutes the perfect path for the evolution of K. pneumoniae isolates causing invasive untreatable infections especially in a country with a high burden of infectious diseases such as Egypt. Therefore there is an imperative need for countrywide surveillances to monitor the prevalence of these superbugs with limited therapeutic options.