TABLE 1.

Distribution of MICs of BAL19403 and comparator drugs for propionibacterial clinical isolates as a function of resistance phenotype

Resistance phenotype and mechanism(s)StrainMIC (μg/ml)a
BAL19403ErythromycinClindamycinTetracycline
Erys Clis TetsSW10≤0.06≤0.060.1250.5
SW16≤0.06≤0.06≤0.060.25
SW17≤0.06≤0.06≤0.060.25
SW26≤0.06≤0.06≤0.060.5
D-04/97≤0.06≤0.060.1251
QK8/97≤0.060.1250.1250.5
EG7NS≤0.06≤0.06≤0.06≤0.06
EG13NS≤0.06≤0.06≤0.061
NCTC11865b≤0.060.125≤0.060.5
Erys Clir Tets,r (unknownc)SW11≤0.060.1250.52
EG3NS≤0.06≤0.060.250.5
SW3CD≤0.06≤0.0681
Eryr Clir Tets,r (G2057A ± G1058C)P95≤0.0640.50.5
P401:5≤0.062132
Eryr Clir Tets,r (A2058G ± G1058C)P425:14>51251216
P429:1 (SC)≤0.0644≥32
P429:1 (BC)0.5281
SW54EA0.5>512320.5
SW101T4>51225632
Eryr Clir Tets,r (A2059G ± G1058C)GE46EBd256>5125121
EG7E0.5>512≥3232
Eryr Clir Tets,r (ErmX)GE4E128>512>5122
SP64E≥256>512>5121
SW101CDA64>512≥512≤0.06
Erys Clis Tetr (G1058C)P:413≤0.06≤0.06≤0.0616
Eryr Clir Tets (unknownc)QK6/92b0.1250.511
Eryr Clir Tetr (unknownc)P322:20.25>512432
  • a The adopted resistance breakpoints are as follows: erythromycin, ≥0.5 μg/ml; clindamycin, ≥0.25 μg/ml; tetracycline, ≥2 μg/ml (26, 27).

  • b P. granulosum; all other strains are P. acnes.

  • c The genetic basis of antibiotic resistance is unknown.

  • d Additional mutations contributing to BAL19403 resistance are unknown.