Limits...
Complete sequences of KPC-2-encoding plasmid p628-KPC and CTX-M-55-encoding p628-CTXM coexisted in Klebsiella pneumoniae.

Wang L, Fang H, Feng J, Yin Z, Xie X, Zhu X, Wang J, Chen W, Yang R, Du H, Zhou D - Front Microbiol (2015)

Bottom Line: A carbapenem-resistant Klebsiella pneumoniae strain 628 was isolated from a human case of intracranial infection in a Chinese teaching hospital.ΔTn3-ISKpn27-bla KPC-2-ΔISKpn6-ΔTn1722 and this transposon together with a mercury resistance (mer) gene locus constitutes a 34 kb acquired drug-resistance region. bla KPC-2 has two transcription starts (nucleotides G and C located at 39 and 250 bp upstream of its coding region respectively) which correspond to two promoters, i.e., the intrinsic P1 and the upstream ISKpn27/Tn3-provided P2 with the core -35/-10 elements TAATCC/TTACAT and TTGACA/AATAAT respectively. bla CTX-M-55 is mobilized in an ISEcp1-bla CTX-M-55-Δorf477 transposition unit and appears to be the sole drug-resistant determinant in p628-CTXM. bla CTX-M-55 possesses a single transcription start (nucleotides G located at 116 bp upstream of its coding region) corresponding to the ISEcp1-provided P1 promoter with the core -35/-10 element TTGAAA/TACAAT.All the above detected promoters display a characteristic of constitutive expression.

View Article: PubMed Central - PubMed

Affiliation: Department of Clinical Laboratory, The First Hospital Affiliated to Henan University Kaifeng, China.

ABSTRACT
A carbapenem-resistant Klebsiella pneumoniae strain 628 was isolated from a human case of intracranial infection in a Chinese teaching hospital. Strain 628 produces KPC-2 and CTX-M-55 encoded by two different conjugative plasmids, i.e., the IncFIIK plasmid p628-KPC and the IncI1 plasmid p628-CTXM respectively. bla KPC-2 is captured by a Tn1722-based unit transposon with a linear structure. ΔTn3-ISKpn27-bla KPC-2-ΔISKpn6-ΔTn1722 and this transposon together with a mercury resistance (mer) gene locus constitutes a 34 kb acquired drug-resistance region. bla KPC-2 has two transcription starts (nucleotides G and C located at 39 and 250 bp upstream of its coding region respectively) which correspond to two promoters, i.e., the intrinsic P1 and the upstream ISKpn27/Tn3-provided P2 with the core -35/-10 elements TAATCC/TTACAT and TTGACA/AATAAT respectively. bla CTX-M-55 is mobilized in an ISEcp1-bla CTX-M-55-Δorf477 transposition unit and appears to be the sole drug-resistant determinant in p628-CTXM. bla CTX-M-55 possesses a single transcription start (nucleotides G located at 116 bp upstream of its coding region) corresponding to the ISEcp1-provided P1 promoter with the core -35/-10 element TTGAAA/TACAAT. All the above detected promoters display a characteristic of constitutive expression. Coexistence of bla KPC and bla CTX-M in K. pneumoniae has been reported many times but this is the first report to gain deep insights into genetic platforms, promoters, and expression of the two coexisting bla genes with determination of entire nucleotide sequences of the two corresponding plasmids.

No MeSH data available.


Related in: MedlinePlus

Linear comparison of blaCTX−M genetic surroundings. Genes are denoted by arrows and colored based on gene function classification.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4541600&req=5

Figure 4: Linear comparison of blaCTX−M genetic surroundings. Genes are denoted by arrows and colored based on gene function classification.

Mentions: R64, p628-CTXM, pKHSB1, and pEK204 carry a 17 kb IS2-based mobile element, a 2980 bp ISEcp1-based transposition unit, a 7935 bp Tn3-based element, and an 8014 bp Tn3-based element respectively; each of them is the sole determinant for antibiotics resistance of the corresponding plasmid (Figure 4). For R64, stepwise insertions occur to eventually assemble the IS2-based element: insertion of IS2 into arsA1, that of Tn6082 into IS2, that of IS1133 into Tn6082, and finally that of Tn10 into IS1133; the tet locus carried by Tn10 and the strAB operon carried by Tn6082 account for resistance to tetracycline and streptomycin respectively.


Complete sequences of KPC-2-encoding plasmid p628-KPC and CTX-M-55-encoding p628-CTXM coexisted in Klebsiella pneumoniae.

Wang L, Fang H, Feng J, Yin Z, Xie X, Zhu X, Wang J, Chen W, Yang R, Du H, Zhou D - Front Microbiol (2015)

Linear comparison of blaCTX−M genetic surroundings. Genes are denoted by arrows and colored based on gene function classification.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4541600&req=5

Figure 4: Linear comparison of blaCTX−M genetic surroundings. Genes are denoted by arrows and colored based on gene function classification.
Mentions: R64, p628-CTXM, pKHSB1, and pEK204 carry a 17 kb IS2-based mobile element, a 2980 bp ISEcp1-based transposition unit, a 7935 bp Tn3-based element, and an 8014 bp Tn3-based element respectively; each of them is the sole determinant for antibiotics resistance of the corresponding plasmid (Figure 4). For R64, stepwise insertions occur to eventually assemble the IS2-based element: insertion of IS2 into arsA1, that of Tn6082 into IS2, that of IS1133 into Tn6082, and finally that of Tn10 into IS1133; the tet locus carried by Tn10 and the strAB operon carried by Tn6082 account for resistance to tetracycline and streptomycin respectively.

Bottom Line: A carbapenem-resistant Klebsiella pneumoniae strain 628 was isolated from a human case of intracranial infection in a Chinese teaching hospital.ΔTn3-ISKpn27-bla KPC-2-ΔISKpn6-ΔTn1722 and this transposon together with a mercury resistance (mer) gene locus constitutes a 34 kb acquired drug-resistance region. bla KPC-2 has two transcription starts (nucleotides G and C located at 39 and 250 bp upstream of its coding region respectively) which correspond to two promoters, i.e., the intrinsic P1 and the upstream ISKpn27/Tn3-provided P2 with the core -35/-10 elements TAATCC/TTACAT and TTGACA/AATAAT respectively. bla CTX-M-55 is mobilized in an ISEcp1-bla CTX-M-55-Δorf477 transposition unit and appears to be the sole drug-resistant determinant in p628-CTXM. bla CTX-M-55 possesses a single transcription start (nucleotides G located at 116 bp upstream of its coding region) corresponding to the ISEcp1-provided P1 promoter with the core -35/-10 element TTGAAA/TACAAT.All the above detected promoters display a characteristic of constitutive expression.

View Article: PubMed Central - PubMed

Affiliation: Department of Clinical Laboratory, The First Hospital Affiliated to Henan University Kaifeng, China.

ABSTRACT
A carbapenem-resistant Klebsiella pneumoniae strain 628 was isolated from a human case of intracranial infection in a Chinese teaching hospital. Strain 628 produces KPC-2 and CTX-M-55 encoded by two different conjugative plasmids, i.e., the IncFIIK plasmid p628-KPC and the IncI1 plasmid p628-CTXM respectively. bla KPC-2 is captured by a Tn1722-based unit transposon with a linear structure. ΔTn3-ISKpn27-bla KPC-2-ΔISKpn6-ΔTn1722 and this transposon together with a mercury resistance (mer) gene locus constitutes a 34 kb acquired drug-resistance region. bla KPC-2 has two transcription starts (nucleotides G and C located at 39 and 250 bp upstream of its coding region respectively) which correspond to two promoters, i.e., the intrinsic P1 and the upstream ISKpn27/Tn3-provided P2 with the core -35/-10 elements TAATCC/TTACAT and TTGACA/AATAAT respectively. bla CTX-M-55 is mobilized in an ISEcp1-bla CTX-M-55-Δorf477 transposition unit and appears to be the sole drug-resistant determinant in p628-CTXM. bla CTX-M-55 possesses a single transcription start (nucleotides G located at 116 bp upstream of its coding region) corresponding to the ISEcp1-provided P1 promoter with the core -35/-10 element TTGAAA/TACAAT. All the above detected promoters display a characteristic of constitutive expression. Coexistence of bla KPC and bla CTX-M in K. pneumoniae has been reported many times but this is the first report to gain deep insights into genetic platforms, promoters, and expression of the two coexisting bla genes with determination of entire nucleotide sequences of the two corresponding plasmids.

No MeSH data available.


Related in: MedlinePlus