리팜피신과 플로로퀴놀론계 항생균제에 내성인 Bifidobacterium infantis OFR-525 균주

Bifidobacterium infantis OFR-525 Strain Resistant to Rifampicin and Fluoroquinolones

Bifidobacterium infantis K-525 isolated from healthy Korean was susceptible to rifampicin and fluoroquinolones and resistant to other antituberculosis agents. When the preparation of this strain is taken as a therapeutics for human intestinal disorders with rifampicin or fluoroquinolones, its therapeutic effect can not be expected. So, B. infantis RFR-525 resistant to rifampicin was obtained by treating the parent B. infantis 525 with N-methyl-N`-nitro-N-nitrosoguanidine. B. infantis OFR-525 was produced by serial passage of B. infantis RFR-525 on agar with 2-fold minimal inhibitory concentration of ofloxacin. B. infantis OFR-525 was resistant to antituberculosis agents and fluoroquinolones up to 4-128 fold higher than that for the original strain. The resistance of B. infantis OFR-525 against rifampicin and ofloxacin was maintained in vivo and in vitro. Conclusively, B. infantis OFR-525 can be regarded as a promising strain which can be developed as the preparation for the treatment of the intestinal disorders of the tuberculosis patients under rifampicin and ofloxacin therapy.