Article Figures & Data
Figures
- FIG 1
Deduced amino acid sequence of PBP3 from H. influenzae NUBL1772 compared to that of strain Rd. Dashes represent identical amino acids. Boxes highlight the three conserved motifs of the active site, specifically, Ser327-Thr-Val-Lys, Ser379-Ser-Asn, and Lys512-Thr-Gly. NUBL1772 was found to have S385T and L389F alterations. The number of amino acids in PBP3 from NUBL1772 with the V525_N526insM insertion was altered and is described in parentheses. The number of amino acids was restored in PBP3 from NUBL1772 with the T591del deletion.
Tables
- TABLE 1
Characterization of seven H. influenzae isolates with reduced carbapenem susceptibility
Isolatea Region of source Biotype Patient information MLSTb PBP3 groupc MIC (μg/ml) Age Sex Source Ampicillin Meropenem Doripenem Imipenem Biapenem NUBL970 Kanagawa II 5 M Nose 1763 II 2 0.06 0.25 4 4 NUBL1767 Ibaragi II 0 F Nose 57 III+ 8 0.12 4 4 8 NUBL1771 Kanagawa V 1 M Nose 1764 III+ 8 1 4 4 8 NUBL1772 Kanagawa II 1 M Nose 57 16 1 4 16 16 NUBL1775 Saitama II 7 F Vagina 1765 III+ 2 1 4 4 8 NUBL1777 Nagano V 7 M Nose 1766 III+ 16 0.12 0.4 2 16 NUBL2814 Chiba II 5 M Nose 1683 II 2 0.25 1 4 8 - TABLE 2
MICs for H. influenzae NUBL1772
Antimicrobial MIC (μg/ml) Rd NUBL1772 Ampicillin 0.25 16 Ampicillin-sulbactam 0.25 16 Amoxicillin 0.5 32 Amoxicillin-clavulanic acid 0.5 32 Cefotaxime 0.06 1 Ceftriaxone ≤0.03 0.25 Cefepime ≤0.25 2 Piperacillin-tazobactam ≤0.03 ≤0.03 Aztreonam 0.06 4 Meropenem 0.03 1 Doripenem 0.06 4 Imipenem 0.5 16 Biapenem 0.5 16 Clarithromycin 8 16 Ciprofloxacin 0.015 0.03 Levofloxacin 0.015 0.03 - TABLE 3
MICs for Rd recombinants carrying ftsI genes related to NUBL1772
Strain or isolatea MIC (μg/ml) Ampicillin Meropenem Doripenem Imipenem Biapenem Rd 0.25 0.03 0.06 0.5 0.5 NUBL1772 16 1 4 16 16 Rd (NUBL1772 ftsI) 8 0.5 2 4 8 Rd (Rd ftsI V525_N526insM) 0.25 0.03 0.06 0.5 0.5 Rd (NUBL1772 ftsI M526del) 2 0.12 0.5 1 2 ↵a Rd recombinants contained the corresponding ftsI genes.
- TABLE 4
Binding of Bocillin FL and β-lactams to recombinant PBP3 proteins
Antimicrobial IC50 (μg/ml) ± SD P value Rd NUBL1772 Ampicillin 0.14 ± 0.03 5.13 ± 1.48 0.028 Meropenem 0.10 ± 0.02 0.15 ± 0.03 0.049 Doripenem 0.12 ± 0.05 0.73 ± 0.33 0.035 Imipenem 0.20 ± 0.15 3.22 ± 0.59 0.001 Biapenem 0.25 ± 0.08 5.86 ± 2.58 0.020 - TABLE 5
Transcription of acrB and efflux pump activity in H. influenzae NUBL1772 compared to that in strain Rd
Strain or isolate Relative mRNA level of acrB P value Initial velocity (fluorescence intensity/min) of ethidium bromide accumulation P value Rd 1.11 ± 0.65 0.038 1.63 ± 0.32 0.026 NUBL1772 4.80 ± 1.98 0.89 ± 0.18
Supplemental material
- Supplemental file 1 -
FIG S1 to S3, Table S1
PDF, 7.1M
- Supplemental file 1 -
