Draft Genome Sequence of a Klebsiella pneumoniae Carbapenemase-Positive Sequence Type 111 Pseudomonas aeruginosa Strain

Abstract

Here, we report the draft genome sequence of a sequence type 111 Pseudomonas aeruginosa strain isolated in 2014 from a patient at the NIH Clinical Center. This P. aeruginosa strain exhibits pan-drug resistance and harbors the blaKPC-2 gene, encoding the Klebsiella pneumoniae carbapenemase enzyme, on a plasmid.

GENOME ANNOUNCEMENT

Pseudomonas aeruginosa is a Gram-negative, opportunistic bacterium that can exhibit high levels of natural resistance, including to antibiotics of last-resort, such as many beta-lactams. P. aeruginosa colonizes the lungs, urinary tract, and skin wounds and consequently puts patients with cystic fibrosis, urinary tract infections, and burn injuries, among other conditions, at the greatest risk (1).

P. aeruginosa strain AATYA was isolated from a perirectal swab collected upon admission of a patient who had previously received hospital care in Colombia, South America. P. aeruginosa AATYA is pan-resistant to antibiotics, including cefepime, ceftazidime, piperacillin-tazobactam, amikacin, tobramycin, gentamicin, levofloxacin, and aztreonam, but is sensitive to colistin. P. aeruginosa AATYA is also resistant to meropenem, imipenem, and doripenem.

Genomic DNA and a sequencing library were prepared from P. aeruginosa AATYA using the Maxwell 16 nucleic acid purification system (Promega) and the Nextera library kit (Illumina). Sequencing was performed on the Illumina MiSeq instrument. The resulting paired-end reads were assembled using SPAdes version 3.5.1 (2). Pilon, a variant detection and assembly refinement tool, was subsequently applied to ensure a minimal assembly error rate (3). The Pilon-improved SPAdes assembly yielded a total of 135 contigs with an N₅₀ of 171,911 bp and an average contig size of 52,616 bp. The largest contig was 720,085 bp.

P. aeruginosa AATYA has a total size of 7,103,193 bp and an average G+C content of 64%. The NCBI Prokaryotic Genome Annotation Pipeline predicted 6,549 protein-coding genes, and 40 genes are suspected to be plasmid-derived. Also identified were 67 pseudogenes, 57 tRNAs, 6 rRNAs, and 4 non-coding RNAs.

Sequence typing of the genome assembly, places P. aeruginosa AATYA in the clinically important ST111 group, considered a high-risk clone (4). There are two published ST111 genomes, a European outbreak strain PA38182 (HG530068) (5) and the Carb 01 63 strain from the Netherlands (CP011317). Those strains, and indeed most carbapenem-resistant ST111 strains, carry the VIM metallo-beta-lactamase, although Klebsiella pneumoniae carbapenemase (KPC)⁺ strains have been reported in Colombia (4, 6). P. aeruginosa AATYA lacks a VIM gene and carries a blaKPC-2 gene in the context of a Tn4401b transposon. The Tn4401b cassette is contained on a single 33,551 bp contig that is present at 2.9-fold coverage relative to the bacterial chromosome and shares some similarity with other Pseudomonas plasmids pCT14 (DQ126685) and pPC9 (CP003739). However, the maximum identity between the AATYA plasmid and the closest reference plasmid, outside the Tn4401a transposon, is 95% and neither pCT14 nor pPC9 carry a blaKPC gene. Transferrable resistance genes are a growing concern in P. aeruginosa (7), and the genome of P. aeruginosa AATYA provides the first genome sequence of an ST111 strain carrying the blaKPC gene on a putative plasmid.

Nucleotide sequence accession numbers.

This whole-genome shotgun project has been deposited at DDBJ/EMBL/GenBank under the accession number LODN00000000. The version described in this paper is the first version, LODN01000000.