Article Figures & Data
Figures
- Fig. 1.
Complete nucleotide sequence and predicted amino acid sequence of the bla CMY-8 β-lactamase gene. The primers for amplification of the gene were synthesized according to the nucleotide sequence of CMY-1 (4, 14) and are double underlined. DNA sequencing was performed with a sequencing primer (underlined) and the PCR primers as well. Arrows indicate the directions of DNA sequencing. The stop codon is indicated with three asterisks. The β-lactamase active site S-V-S-K, the conserved triad K-T-G, and the class C typical motif Y-X-N are underlined.
- Fig. 2.
Alignment of deduced amino acid sequences of CMY-8 with those of CMY-1 and MOX-1. Identical amino acids are marked with dots. The stop codon is indicated with an asterisk. The β-lactamase active site S-V-S-K, the conserved triad K-T-G, and the class C typical motif Y-X-N are shown in boldface type.
- Fig. 3.
PFGE of XbaI-digested genomic DNAs from 19 ESBL-producing K. pneumoniae isolates. Lanes 1, 12, 13, and 23, bacteriophage lambda DNA concatemers (GibcoBRL, Gaithersburg, Md.) which served as molecular size marker; lanes 2 to 11 and 14 to 22, isolates V293, D155, B657, C106, O574, R549, O787, W142, W580, T384, X386, C097, Q381, T923, T386, R436, T986, B262, and T255, respectively. Isolate S276 is not shown here. All ESBL producers except for three isolates carrying CMY-8 (W142, W580, and T384) had different PFGE patterns.
Tables
- Table 1.
MICs for K. pneumoniae strains with different resistance phenotypes and their transconjugantsa
Resistance phenotype group No. of clinical isolates MIC (μg/ml) of drug for clinical isolates No. of transconjugants MIC (μg/ml) of drug for transconjugants AMP AMC CAZ CTX FOX IPM AMP AMC CAZ CTX FOX IPM I 14 >256 4–8 ≥256 3–16 3–16 0.125–0.25 11 >256 4–8 ≥256 6–16 2–6 0.125–0.25 II 2 >256 4–8 2–24 128–256 8–16 0.125 2 >256 4–8 2–3 128–256 8–16 0.125 III 3 >256 16 96 >256 >256 0.25–0.5 3 >256 24 32–64 >256 >256 0.25–0.5 IV 1 >256 12 >256 48 >256 0.5 1 >256 12 >256 8 >256 0.125 ↵a MICs were determined by the E test. Abbreviations: AMP, ampicillin; AMC, amoxicillin-clavulanic acid combination, CAZ, ceftazidime; CTX, cefotaxime; FOX, cefoxitin; IPM, imipenem.
- Table 2.
Results of IEF, genotyping of β-lactamases, plasmid analysis, and PFGE
Resistance phenotype group and strain Clinical isolate Transconjugantc pI(s) SHV TEM AmpC Plasmid profile PFGE pattern pI SHV AmpC Approx plasmid size (kb) Group I X386 8.2, 7.6 5 A I 8.2 5 100 C097 8.2, 7.6, 5.4 5 1 B II 8.2 5 100 Q381 8.2, 7.6, 5.4 5 1 C III 8.2 5 70 T923a 8.2, 7.6, 5.4 5 1 D IV T386 8.2, 7.6, 5.4 12 1 E V 8.2 12 70 R436 8.2, 7.6, 5.4 12 1 E VI 8.2 12 100 S276 8.2, 7.6, 5.4 12 1 F VII 8.2 12 100 T986 8.2, 7.6, 5.4 12 1 G VIII 8.2 12 70 B262a 8.2, 7.6, 5.4 12 1 H IX T255a 8.2, 7.6, 5.4 12 1 I X V293 8.2, 7.6, 5.4 12 1 G XI 8.2 12 70 D155 8.2, 7.6 12 J XII 8.2 12 40 B657 8.2, 7.6 12 K XIII 8.2 12 75 C106 8.2, 7.6 12 J XIV 8.2 12 40 Group II O574 8.3, 7.6, 5.4 11 1 L XV 8.3 95 R549 8.3, 7.6, 5.4 11 1 M XVI 8.3 125 Group III W142 8.25, 7.6, 5.4 11 1 CMY-8 N XVII 8.25 CMY-8 25 W580 8.25, 7.6, 5.4 11 1 CMY-8 N XVII 8.25 CMY-8 25 T384 8.25, 7.6, 5.4 11 1 CMY-8 N XVII 8.25 CMY-8 25 Group IV O787 8.2, 7.6, 5.4 12 1 UDb O XVIII 8.2 12 UD 150
