Rapid and specific detection, molecular epidemiology, and experimental virulence of the O16 subgroup within Escherichia coli sequence type 131

摘要: Escherichia coli sequence type 131 (ST131), a widely disseminated multidrug-resistant extraintestinal pathogen, typically exhibits serotype O25b:H4. However, certain ST131 isolates exhibit O16:H5 and derive from phylogenetic clade that is distinct the classic O25b:H4 clade. Both clades are assigned to by Achtman multilocus typing (MLST) system screening PCR assay targets ST131-specific polymorphisms in mdh gyrB genes. they classified as separate STs Pasteur Institute MLST system, an method O25b rfb region polymorphism pabB detects only O25b-associated Here, we describe novel PCR-based allows for rapid specific detection of O16-associated The members uniformly contained allele 41 fimH (type 1 fimbrial adhesin) narrow range alleles gyrA parC (fluoroquinolone target genes). virulence genotypes resembled those isolates; representative were variably lethal mouse subcutaneous sepsis model. Several pulsotypes spanned multiple sources (adults, children, pets, human fecal samples) locales. An analysis recent clinical E. collections showed O16 globally distributed, accounts 5% overall, and, when compared with other isolates, it associated resistance ampicillin, gentamicin, trimethoprim-sulfamethoxazole susceptibility fluoroquinolones extended-spectrum cephalosporins. Attention this clade, which facilitated our assay, warranted future epidemiological studies conceivably, applications.