A novel Tn1696-like composite transposon (Tn6404) harboring blaIMP-4 in a Klebsiella pneumoniae isolate carrying a rare ESBL gene blaSFO-1

作者：Zhou, Kai; Yu, Wei; Shen, Ping; Lu, Haifeng; Wang, Baohong; Rossen, John W. A.; Xiao, Yonghong^*

来源：Scientific Reports, 2017, 7(1): 17321.

DOI：10.1038/s41598-017-17641-2

• METALLO-BETA-LACTAMASE
• ESCHERICHIA-COLI
• CONJUGATIVE PLASMID
• NUCLEOTIDE-SEQUENCE
• BIOFILM FORMATION
• HIGH PREVALENCE
• CHINA
• IMP-4
• RESISTANCE
• AUSTRALIA

Genetic determinants of a clinical Klebsiella pneumoniae isolate (KP1814) coproducing IMP-4 and a rare ESBL gene SFO-1 was investigated. KP1814 belongs to a novel sequence type (ST) assigned to ST2270. WGS identified four circular DNA sequences in KP1814, including two multidrug-resistance (MDR) plasmids, one virulence plasmid, and one circular form. The MDR plasmid pKP1814-1 (299.9 Kb) is untypeable, and carries two large mosaic multiresistance regions (MRRs). bla(SFO-1) and bla(IMP-4) co-exists on MRR1, and bla(SFO-1) is associated with an IS/Tn-independent genetic context. bla(IMP-4) is carried by a novel In804-like integron (intlI-bla(IMP-4)-Kl.pn.I3-qacG2-aacA4-catB3 Delta) associated with a novel Tn1696-like transposon (designed Tn6404) flanked by IS5075. The other MDR plasmid pKP1814-3 is a 95,701-bp IncFII plasmid, and is a hybrid of a Shigella flexneri plasmid pSF07201 and an E. coli plasmid pCA08. All resistance genes of pKP1814-3 were detected in a similar to 16-kb IS26-flanked composite transposon carried by a Tn5396 transposon. The circular form (18.3 Kb) was composed of two parts belonging to pKP1814-1 and pKP1814-3, respectively. The plasmid pKP1814-2, carrying multiple virulence factors, encodes IncFIB(K) and IncFII(K) replicons with a size of 187,349 bp. The coexistence of MDR and virulence plasmids largely enhances the bacterial fitness in the host and environment.

• 出版日期2017-12-11
• 单位浙江省人民医院; 浙江大学