AUTHOR=Galetti Renata , Andrade Leonardo Neves , Varani Alessandro M. , Darini Ana Lúcia Costa 

TITLE=A Phage-Like Plasmid Carrying blaKPC-2 Gene in Carbapenem-Resistant Pseudomonas aeruginosa

JOURNAL=Frontiers in Microbiology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2019.00572

DOI=10.3389/fmicb.2019.00572

ISSN=1664-302X

ABSTRACT=<p><bold>Background:</bold> Lateral gene transfer plays a central role in the dissemination of carbapenem resistance in bacterial pathogens associated with nosocomial infections, mainly <italic>Enterobacteriaceae</italic> and <italic>Pseudomonas aeruginosa</italic>. Despite their clinical significance, there is little information regarding the mobile genetic elements and mechanism of acquisition and propagation of lateral genes in <italic>P. aeruginosa</italic>, and they remain largely unknown.</p><p><bold>Objectives:</bold> The present study characterized the genetic context of <italic>bla</italic><sub>KPC-2</sub> in carbapenem-resistant <italic>P. aeruginosa</italic> strain BH9.</p><p><bold>Methods:</bold><italic>Pseudomonas aeruginosa</italic> BH9 sequencing was performed using the long-read PacBio SMRT platform and the Ion Proton System. <italic>De novo</italic> assembly was carried out using the SMRT pipeline and Canu, and gene prediction and annotation were performed using Prokka and RAST.</p><p><bold>Results:</bold><italic>Pseudomonas aeruginosa</italic> BH9 exhibited a 7.1 Mb circular chromosome. However, the <italic>bla</italic><sub>KPC-2</sub> gene is located in an additional contig composed by a small plasmid pBH6 from <italic>P. aeruginosa</italic> strain BH6 and several phage-related genes. Further analysis revealed that the beginning and end of the contig contain identical sequences, supporting a circular plasmid structure. This structure spans 41,087 bp, exhibiting all the Mu-like phage landmarks. In addition, 5-bp direct repeats (GGATG) flanking the pBH6 ends were found, strongly indicating integration of the Mu-like phage into the pBH6 plasmid. Mu phages are commonly found in <italic>P. aeruginosa</italic>. However, for the first time showing a potential impact in shaping the vehicles of the dissemination of antimicrobial (e.g., plasmid pBH6) resistance genes in the <italic>Pseudomonas</italic> genus.</p><p><bold>Conclusion:</bold> pBH6 captured the Mu-like Phage BH9, creating a co-integrate pBH6::Phage BH9, and this phage-plasmid complex may represent novel case of a phage-like plasmid.</p>