A total of 1878 non-duplicate clinical Escherichia coli isolates (comprising 1711 urinary isolates and 167 blood-culture isolates), which were collected from multiple centres in Hong Kong during 1996–2008, were used to investigate the prevalence and molecular epidemiology of plasmid-mediated fosfomycin (fos) resistance genes. Eighteen of the 1878 clinical E. coli isolates were fosfomycin resistant, of which six were fosA3 positive and two were positive for another fosA variant (designated fosKP96). No isolates had the fosC2 gene. The clones of the eight isolates were diverse: sequence type (ST) 95 (n = 2), ST118 (n = 1), ST131 (n = 1), ST617 (n = 1), ST648 (n = 1), ST1488 (n = 1) and ST2847 (n = 1). In the isolates, fosA3 and blaCTX-M genes were co-harboured on conjugative plasmids with F2:A−:B− (n = 2), N (n = 1), F–:A−:B1 and N (n = 1) and untypable (n = 2) replicons. Both fosKP96-carrying plasmids belonged to replicon N. RFLP analysis showed that the two F2:A−:B− plasmids carrying fosA3 and blaCTX-M-3 genes shared the same pattern. Complete sequencing of one of the two F2:A−:B− plasmids, pFOS-HK151325 (69 768 bp) demonstrated it to be >99 % identical to the previously sequenced plasmid pHK23a originating from a pig E. coli isolate in the same region. This study demonstrated the dissemination of fosA3 genes in diverse E. coli clones on multiple blaCTX-M-carrying plasmid types, of which F2:A−:B− plasmids closely related to pHK23a were shared by isolates from human and animal sources.
AzizR. K., BartelsD., BestA. A., DeJonghM., DiszT., EdwardsR. A., FormsmaK., GerdesS., GlassE. M.other authors2008; The RAST Server: rapid annotations using subsystems technology. BMC Genomics 9:75 [View Article][PubMed]
GuptaK., HootonT. M., NaberK. G., WulltB., ColganR., MillerL. G., MoranG. J., NicolleL. E., RazR.other authors2011; International clinical practice guidelines for the treatment of acute uncomplicated cystitis and pyelonephritis in women: a 2010 update by the Infectious Diseases Society of America and the European Society for Microbiology and Infectious Diseases. Clin Infect Dis 52:e103–e120 [View Article][PubMed]
HoP. L., YipK. S., ChowK. H., LoJ. Y., QueT. L., YuenK. Y.2010; Antimicrobial resistance among uropathogens that cause acute uncomplicated cystitis in women in Hong Kong: a prospective multicenter study in 2006 to 2008. Diagn Microbiol Infect Dis 66:87–93 [View Article][PubMed]
HoP. L., LoW. U., YeungM. K., LiZ., ChanJ., ChowK. H., YamW. C., TongA. H., BaoJ. Y.other authors2012a; Dissemination of pHK01-like incompatibility group IncFII plasmids encoding CTX-M-14 in Escherichia coli from human and animal sources. Vet Microbiol 158:172–179 [View Article][PubMed]
HouJ., HuangX., DengY., HeL., YangT., ZengZ., ChenZ., LiuJ. H.2012; Dissemination of the fosfomycin resistance gene fosA3 with CTX-M β-lactamase genes and rmtB carried on IncFII plasmids among Escherichia coli isolates from pets in China. Antimicrob Agents Chemother 56:2135–2138 [View Article][PubMed]
JohnsonT. J., BielakE. M., FortiniD., HansenL. H., HasmanH., DebroyC., NolanL. K., CarattoliA.2012; Expansion of the IncX plasmid family for improved identification and typing of novel plasmids in drug-resistant Enterobacteriaceae. Plasmid 68:43–50 [View Article][PubMed]
LoW. U., HoP. L., ChowK. H., LaiE. L., YeungF., ChiuS. S.2010; Fecal carriage of CTXM type extended-spectrum β-lactamase-producing organisms by children and their household contacts. J Infect 60:286–292 [View Article][PubMed]
SekizukaT., MatsuiM., YamaneK., TakeuchiF., OhnishiM., HishinumaA., ArakawaY., KurodaM.2011; Complete sequencing of the blaNDM-1-positive IncA/C plasmid from Escherichia coli ST38 isolate suggests a possible origin from plant pathogens. PLoS ONE 6:e25334 [View Article][PubMed]
WachinoJ., YamaneK., SuzukiS., KimuraK., ArakawaY.2010; Prevalence of fosfomycin resistance among CTX-M-producing Escherichia coli clinical isolates in Japan and identification of novel plasmid-mediated fosfomycin-modifying enzymes. Antimicrob Agents Chemother 54:3061–3064 [View Article][PubMed]
ZhouY., YuH., GuoQ., XuX., YeX., WuS., GuoY., WangM.2010; Distribution of 16S rRNA methylases among different species of Gram-negative bacilli with high-level resistance to aminoglycosides. Eur J Clin Microbiol Infect Dis 29:1349–1353 [View Article][PubMed]