TABLE 3.

MICs for P. gingivalis wild-type, galE, and galE-c strains

AntibioticMIC (μg/ml)a for:
33277 (wild type)galE straingalE-c strain
Benzylpenicillin0.011 ± 0.00230.0047 ± 0.0012b0.0073 ± 0.0012
Oxacillin0.10 ± 0.0200.053 ± 0.010b0.084 ± 0.017
Ampicillin<0.016<0.016<0.016
Cefotaxime0.0067 ± 0.00120.002 ± 0.00b0.006 ± 0.002c
Ceftriaxone<0.002<0.002<0.002
Imipenem0.084 ± 0.0350.024 ± 0.0080b0.043 ± 0.018
Tetracycline0.042 ± 0.00870.037 ± 0.00871.7 ± 0.29d
Erythromycin<0.016>256e<0.016
Clindamycin<0.016>256e<0.016
Kanamycin>256>256>256
Tobramycin>256>256>256
Vancomycin12 ± 41.8 ± 0.29b4 ± 0c
  • a Values are shown as means ± standard deviations.

  • b The galE strain had significant difference in sensitivity to the indicated antibiotic compared to the wild-type 33277.

  • c The galE-c strain had significant difference in sensitivity to the indicated antibiotic compared to the ΔgalE strain.

  • d Resistance was dependent on insertion of tetQ.

  • e Resistance was dependent on insertion of ermF.