Virulence, antimicrobial susceptibility and phylogenetic analysis of Cronobacter sakazakii isolates of food origins from Jordan.

AIMS

The aim was to characterize a collection of Cronobacter sakazakii isolates collected from various origins in Jordan.

METHODS AND RESULTS

The isolates were characterized using 16S rRNA sequencing, DNA microarray, multi-locus sequence typing (MLST), O-serotyping, virulence gene identification and antibiotic susceptibility testing. The identities and phylogenetic relatedness revealed that C. sakazakii sequence type 4 (ST4) and Csak O:1 serotype were the most prevalent STs and serovars amongst these C. sakazakii strains. PCR screening of putative virulence genes showed that the siderophore-interacting protein gene (sip) and iron acquisition gene clusters (eitCBAD and iucABCD/iutA) were the most detected genes with noticeable variability in the type 6 secretion system (T6SS) and filamentous hemagglutinin/adhesion (FHA) gene loci. The antibiotic resistance profiles revealed that the majority of the isolates were susceptible to all antibiotics used despite harbouring a class C β-lactamase resistance gene.

CONCLUSIONS

The results described in this report provide additional insights about the considerable genotypic and phenotypic heterogeneity within C. sakazakii.

SIGNIFICANCE AND IMPACT OF THE STUDY

The information reported in this study might be of great value in understanding the origins of C. sakazakii isolates, in addition to their diversity and variability, which might be helpful in preventing future outbreaks of this pathogen.