Isolation and identification of one strain of Pseudomonas fulva and phylogenetic analysis

OBJECTIVE To analyze a strain of multidrug-resistant Pseudomonas fulva by whole genome sequencing, investigate the genomic characteristics and analyze the significance in phyletic evolution.

METHODS A strain of P.fulva, NY4814, was isolated from the Chinese PLA General Hospital in 2014. The genome sequence data of the strain were obtained after the purification, preservation and whole genome sequencing. The specie of the strain was identified by comparing with average nucleotide identity (ANI); the minimum inhibitory concentrations (MIC) of the strains were determined by VITEK2 system. All of the data regarding to the genomic sequences of P. fulva were downloaded from RefSeq database of National Center of Biotechnology Information (NCBI) to construct the phylogenetic tree.

RESULTS The P. fulva NY4814 was resistant to carbapenems and quinolones. The chromosome carried a newly discovered Tn7675 unit transposon, which mediated resistance to aminoglycosides and chloramphenicol. Simultaneously, the plasmid pNY4814-IMP drove the wide dissemination of the bla_IMP resistance gene across Pseudomonas species via a highly conserved conjugative and transfer mechanism, and the Tn6485i unit transposon carried by the chromosome mediated the resistance to β-lactams.

CONCLUSIONS As one of the potential carriers for the transmission of carbapenems resistance genes and other types of drug resistance genes, the P. fulva leads to the infection as a seldom opportunistic pathogen. The genetic structure of NY4814 and its association with genetic evolution of the species are observed in the study, which intensify the understanding of the species and provide theoretical bases for prevention and monitoring of bacterial infections.