ColE1-Like Plasmid pIP843 of Klebsiella pneumoniae Encoding Extended-Spectrum β-Lactamase CTX-M-17

Abstract

The resistance of Klebsiella pneumoniae BM4493, isolated in Ho Chi Minh City, Vietnam, to cefotaxime and aztreonam was due to production of a novel ␤-lactamase, CTX-M-17. The bla CTX-M-17 gene was borne by 7,086-bp plasmid pIP843, which was entirely sequenced and which was found to belong to the ColE1 family. The 876-bp bla CTX-M-17 gene differed from bla CTX-M-14 by 2 nucleotides, which led to the single amino acid substitution Glu2893Lys. bla CTX-M-17 was flanked upstream by an ISEcp1-like element and downstream by an insertion sequence (IS) IS903 variant designated IS903-C. The transcriptional start site of bla CTX-M-17 was located 109 nucleotides upstream from the initiation codon in the ISEcp1-like element, which also provided the promoter sequences. Plasmid pIP843, which was non-self-transferable and nonmobilizable, contained five open reading frames transcribed in the same orientation. Regions homologous to sequences coding for putative RNA II and RNA I transcripts, a rom gene, which is involved in initiation of replication, and a cer-like gene, which is responsible for the stability of ColE1-like plasmids, were identified. Consensus sequences for putative replication (oriV) and transfer (oriT) origins were present. Results of primer extension experiments indicated that ISEcp1 provides the promoter for expression of bla CTX-M-17 and may contribute to dissemination of this gene.

Prevalence and Molecular Epidemiology of CTX-MExtended-Spectrum β-Lactamase-Producing Escherichia coli and Klebsiella pneumoniae in RussianHospitals

“…This observation is in good agreement with the previous publication of Bradford et al (10) reporting the location of genes encoding CTX-M-5 on small non-self-transferable plasmids. It may also explain the relatively low proportion of CTX-M-5-producing isolates compared to those bearing CTX-M-3 and Neither CTX-M-8-nor CTX-M-9-related enzymes were found in this study, although in recent years ESBLs of the latter genetic group were found in other European countries (Spain [9,11,35], France [18,36], and the United Kingdom [Alobwede et al, letter]) as well as in Asian countries (Japan [41], China [14], Taiwan [22,44], Korea [28], and Vietnam [13]) and Brazil (8).…”

“…PCR has been used widely to detect bla CTX-M genes, but detection of all the known variants usually required multiple reactions with specific primers for different genes (12,14). Consensus CTX-M primers have also been described (13,36), but these primers were used for amplification of bla CTX-M genes from a limited number of isolates. Consequently, very few studies have assessed countrywide prevalence of ESBLs which belong to the distinct CTX-M clusters (N. Shibata, Y. Doi, K. Shibayama, T. Yagi, and Y. Arakawa, Abstr.…”

Emergence of CTX-M-15 type extended-spectrum β-lactamase-producing Salmonella spp. in Kuwait and the United Arab Emirates

“…Different elements may be involved in the mobilization of bla CTX-M genes. Studies with plasmids have confirmed the potential involvement of the insertion sequence ISEcp1 in the mobility of bla CTX-M (Cao et al, 2002). CTX-M enzymes comprise a rapidly growing family of enzymes disseminated in several parts of the world (Bonnet, 2004).…”

“…ESBL-producing strains were analyzed by PCR to detect the presence of bla CTX-M , bla SHV and bla TEM genes. PCR amplification was performed using published primer pairs (Cao et al, 2002), which are as follows: MA-1 59-SCS ATG TGC AGY ACC AGT AA-39 and MA-2 59-CCG CRA TAT GRT TGG TGG TG-39 (for bla CTX-M ), OS-5 59-TTA TCT CCC TGT TAG CCA CC-39 and OS-6 59-GAT TTG CTG ATT TCG CTC GG-39 (for bla SHV ), and C 59-TCG GGG AAA TGT GCG CG-39 and D 59-TGC TTA ATC AGT GAG GCA CC-39 (bla TEM ). PCR was carried out with the buffer supplied by the manufacturer using 1 ml each primer and 0.25 ml Taq polymerase [5 U (ml PE) 21 ] (GeneAmp Gold PCR reagent kit; Applied Biosystems).…”

Survey for β-lactamase among bacterial isolates from Guangzhou, China hospitals between 2005–2006

“…3 The movement of transposons, such as ISEcp1B, may promote resistance to gene evolution. 14,15 The identification of a new CTX-M ESBLs gene subtype, the ISEcp1B/IS903 hybrid, which is a composite of known insertion sequences is evidence that evolution is occurring during these horizontal transfers. Similar composite transposons consisting of ISEcp1B and IS903 flanking the CTX-M-1, CTX-M-9, CTX-M-15, CTX-M-17 and CTX-M-54 genes, were reported in Europe, the Americas and Asia.…”