ISOLATION AND CHARACTERIZATION OF HUMAN-DERIVED blaKPC-3-PRODUCING SALMONELLA ENTERICA SEROVAR RISSEN IN 2018

Authors    Fortini D, García-Fernández A, Lucarelli C, Dionisi A M, Arena S, Owczarek S, Equestre M, Carattoli A, Sacco F, Rossi S, Ortenzi R, Primavilla S, Villa L

Abstract    In this study, we describe a Salmonella enterica serovar (S.) Rissen strain with a reduced susceptibility to meropenem, isolated from a urinary infection in an 89-year-old woman in 2018 during activity surveillance in Italy (Enter-Net Italia). The genomic characteristics, pathogenicity, and antimicrobial resistance mechanisms were investigated via a genomic approach. Antimicrobial susceptibility testing revealed a "susceptible, increased exposure" phenotype to meropenem in the S. Rissen strain (4_29_19). Whole-genome sequencing (WGS) was performed using both the NovaSeq 6000 S4 PE150 XP platform (Illumina, San Diego, CA, USA) and MinION (Oxford Nanopore). The S. Rissen 4_29_19 strain harboured two plasmids: a pKpQIL-like plasmid carrying the bla_KPC-3 resistance gene in a Tn4401a transposon (pKPC_4_29_19), and a ColE-like plasmid (p4_4_29_19) without resistance genes, highly prevalent among Enterobacterales. Comparative analysis revealed that the pKPC_4_29_19 plasmid was highly related to the pKpQIL reference plasmid (GU595196), with 57 % coverage and 99.96 % identity, but lacking a region of about 30 kb, involving the FIIK_2 replicon region and the entire transfer locus, causing the loss of its ability to conjugate. To our knowledge, this is the first time that a pKpQIL-like plasmid, carrying bla_KPC-3, highly diffused in Klebsiella pneumoniae strains, has been identified in a Salmonella strain in our country. The acquisition of bla_KPC genes by Salmonella spp. is extremely rare, and is reported only sporadically. In zoonotic bacteria isolated from humans, the presence of a carbapenem resistance gene carried by mobile genetic elements, usually described in healthcare-associated infection bacteria, represents an important concern for public health.

Publish Date  2023

Volume    12 (9)

ISSN        2079-6382

DOI          doi.org/10.3390/antibiotics12091377

URL         https://www.mdpi.com/2079-6382/12/9/1377

Journal    Antibiotics

Pages      art. n. 1377

PMID       37760674