Abstract
BackgroundThe Brazilian endemic clone Pseudomonas aeruginosa ST277 carries important antibiotic resistance determinants, highlighting the gene coding for SPM-1 carbapenemase. However, the resistance and persistence of this clone is apparently restricted to the Brazilian territory. To understand the differences between Brazilian strains from those isolated in other countries, we performed a phylogenetic analysis of 47 P. aeruginosa ST277 genomes as well as analyzed the virulence and resistance gene profiles. Furthermore, we evaluated the distribution of genomic islands and assessed in detail the characteristics of the CRISPR-Cas immunity system in these isolates.ResultsThe Brazilian genomes presented a typical set of resistance and virulence determinants, genomic islands and a high frequency of the CRISPR-Cas system type I-C. Even though the ST277 genomes are closely related, the phylogenetic analysis showed that the Brazilian strains share a great number of exclusively SNPs when compared to other ST277 genomes. We also observed a standard CRISPR spacers content for P. aeruginosa ST277, confirming a strong link between sequence type and spacer acquisition. Most CRISPR spacer targets were phage sequences.ConclusionsBased on our findings, P. aeruginosa ST277 strains circulating in Brazil characteristically acquired In163 and PAGI-25, which can distinguish them from strains that do not accumulate resistance mechanisms and can be found on the Asian, European and North American continents. The distinctive genetic elements accumulated in Brazilian samples can contribute to the resistance, pathogenicity and transmission success that characterize the ST277 in this country.
Highlights
The Brazilian endemic clone Pseudomonas aeruginosa ST277 carries important antibiotic resistance determinants, highlighting the gene coding for SPM-1 carbapenemase
SPM-1-producing P. aeruginosa has been mainly isolated from nosocomial settings, reports of this multidrug-resistant bacterium in urban rivers and microbiota of migratory birds in Brazil alert to the Silveira et al BMC Genomics (2020) 21:255 dispersion of this important resistance mechanism [5, 6]
Besides SPM-1, other genetic determinants have been associated with ST277: i) the class 1 integron In163 carrying three resistance genes; ii) rmtD gene that confers high-level resistance to most aminoglycosides; and iii) the type I-C of Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR) and associated proteins [9,10,11]
Summary
The Brazilian endemic clone Pseudomonas aeruginosa ST277 carries important antibiotic resistance determinants, highlighting the gene coding for SPM-1 carbapenemase. To understand the differences between Brazilian strains from those isolated in other countries, we performed a phylogenetic analysis of 47 P. aeruginosa ST277 genomes as well as analyzed the virulence and resistance gene profiles. SPM-1-producing P. aeruginosa has been mainly isolated from nosocomial settings, reports of this multidrug-resistant bacterium in urban rivers and microbiota of migratory birds in Brazil alert to the Silveira et al BMC Genomics (2020) 21:255 dispersion of this important resistance mechanism [5, 6]. Most SPM-1-producing P. aeruginosa strains descend from a common ancestor, a clone belonging to ST277 [2]. Besides SPM-1, other genetic determinants have been associated with ST277: i) the class 1 integron In163 carrying three resistance genes (aacA4, blaOXA-56 and aadA7); ii) rmtD gene that confers high-level resistance to most aminoglycosides; and iii) the type I-C of Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR) and associated proteins [9,10,11]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
