TABLE 1.

IC50 and Ki (preincubation) values (μM) of clavulanic acid and AM-112 against isolated β-lactamase enzymes

Enzyme (group/classa) and inhibitorIC50Ki (pre-inc.b)
E. coli
    TEM-1 (2b/A)
        Clavulanic acid0.127.1 × 10−4
        AM-1122.260.014
    TEM-10 (2be/A)
        Clavulanic acid0.032.5 × 10−5
        AM-1120.2245.6 × 10−5
    SHV-5 (2be/A)
        Clavulanic acid0.0081 × 10−5
        AM-1120.162 × 10−4
E. cloacae
    P99 (1/C)
        Clavulanic acid110.009
        AM-1120.0021.6 × 10−6
S. marcescens
    S2 (1/C)
        Clavulanic acid3270.15
        AM-1120.073 × 10−5
P. aeruginosa
    S + A (1/C)
        Clavulanic acid4490.086
        AM-1120.0023.6 × 10−7
E. coli
    OXA-1 (2d/D)
        Clavulanic acid992.3
        AM-1120.0051.1 × 10−4
    OXA-5 (2d/D)
        Clavulanic acid2020.322
        AM-1120.00071 × 10−6
  • a Group, Bush-Jacoby-Medeiros classification (4); class, Ambler classification (1).

  • b pre-inc., preincubation.