Table 3.

Frequency of spontaneous and oxidant-induced mutations

B. fragilisstrainFrequency of mutations (no. of fusidic acid-resistant colonies/109 cells plated)a
Spontaneous (control)Induced by:
No addition50 μM TBHP50 μM CHP
IB260 (katB)
IB274 (ahpCF)4.85.268NDb
IB276 (ahpF)6.87.413.2192
IB281 (ahpCF katB)8.18.619.0199
  • a Average of two determinations. TBHP,t-butyl hydroperoxide; CHP, cumene hydroperoxide.

  • b ND, not determined due to bacterial cell lysis.