AUTHOR=Vázquez Xenia , Fernández Javier , Bances Margarita , Lumbreras Pilar , Alkorta Miriam , Hernáez Silvia , Prieto Elizabeth , de la Iglesia Pedro , de Toro María , Rodicio M. Rosario , Rodicio Rosaura 

TITLE=Genomic Analysis of Ciprofloxacin-Resistant Salmonella enterica Serovar Kentucky ST198 From Spanish Hospitals

JOURNAL=Frontiers in Microbiology

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.720449

DOI=10.3389/fmicb.2021.720449

ISSN=1664-302X

ABSTRACT=<p><italic>Salmonella enterica</italic> serovar Kentucky (<italic>S</italic>. Kentucky) with sequence type (ST) 198 and highly resistant to ciprofloxacin (ST198-Cip<sup><italic>R</italic></sup>) has emerged as a global MDR clone, posing a threat to public health. In the present study, whole genome sequencing (WGS) was applied to characterize all Cip<sup><italic>R</italic></sup><italic>S.</italic> Kentucky detected in five Spanish hospitals during 2009–2018. All Cip<sup><italic>R</italic></sup> isolates (<italic>n</italic> = 13) were ST198 and carried point mutations in the quinolone resistance-determining regions (QRDRs) of both <italic>gyrA</italic> (resulting in Ser83Phe and Asp87Gly, Asp87Asn, or Asp87Tyr substitutions in GyrA) and <italic>parC</italic> (with Thr57Ser and Ser80Ile substitutions in ParC). Resistances to other antibiotics (ampicillin, chloramphenicol, gentamicin, streptomycin, sulfonamides, and tetracycline), mediated by the <italic>bla</italic><sub><italic>TEM–</italic></sub><sub>1</sub><sub><italic>B</italic></sub>, <italic>catA1, aacA5</italic>, <italic>aadA7, strA</italic>, <italic>strB</italic>, <italic>sul1</italic>, and <italic>tet</italic>(A) genes, and arranged in different combinations, were also observed. Analysis of the genetic environment of the latter resistance genes revealed the presence of multiple variants of SGI1 (<italic>Salmonella</italic> genomic island 1)-K and SGI1-P, where all these resistance genes except <italic>catA1</italic> were placed. IS<italic>26</italic> elements, found at multiple locations within the SGI1 variants, have probably played a crucial role in their generation. Despite the wide diversity of SGI1-K- and SGI1-P-like structures, phylogenetic analysis revealed a close relationship between isolates from different hospitals, which were separated by a minimum of two and a maximum of 160 single nucleotide polymorphisms. Considering that <italic>S. enterica</italic> isolates resistant to fluoroquinolones belong to the high priority list of antibiotic-resistant bacteria compiled by the World Health Organization, continuous surveillance of the <italic>S</italic>. Kentucky ST198-CIP<sup><italic>R</italic></sup> clone is required.</p>