Genetic analysis of a PER-2 producing Shewanella spp. strain harboring a variety of mobile genetic elements and antibiotic resistant determinants.

ALMUZARA M, MONTAÑA S, LAZZARO T, UONG S, PARMECIANO DI NOTO G, TRAGLIA G, BAKAI R, CENTRÓN D, IRIARTE A, QUIROGA C, RAMIREZ MS.

Journal of Global Antimicrobial Resistance

Elsevier

Lugar: Amsterdam; Año: 2017

OBJECTIVE: The goal of this work is to investigate the molecular mechanisms that explain the multidrug resistant phenotype found in a novel clinical Shewanella spp. strain (Shew256) recovered from a diabetic patient.METHODS: The whole-genome shotgun sequencing was obtained with Illumina MiSeq-I and Nextera XT DNA library. De novo assembly was performed with SPADES. RAST was used to predict the open reading frames and the predictions were confirmed using BLAST. Further genomic analysis was carried out using average nucleotide identity (ANI), ACT (Artemis), OrthoMCL, ARG-ANNOT, ISFinder, PHAST, tRNAscan-SE, plasmidSPAdes, PlasmidFinder and MAUVE. PCR reactions and plasmid extraction were also performed.RESULTS: The genomic analysis revealed a total of 456 predicted genes, which are unique to Shew256 when compared with the other Shewanella genomes. Moreover, the presence of different resistance genes, including the presence of a blaPER-2, were found. A complex class 1 integron containing the ISCR1 gene, disrupted by two putative transposase genes were identified. Furthermore, other resistance genes, a transposon containing aph(3´), insertion sequences, phages, and non-coding RNAs were also found.CONCLUSION: Evidences of acquisition of resistance genes and mobile elements that could explain the multidrug resistance phenotype were observed. This Shewanella species represents a prime example of how antibiotic resistance determinants can be acquired by uncommon pathogens.