Mechanism of streptomycin resistance in Leptospira biflexa strain Urawa.

The mechanism of streptomycin resistance of Leptospira biflexa was investigated. A streptomycin-resistance mutant of Leptospira showed cross-resistance to dihydrostreptomycin but not to other antibiotics. Enzymatic inactivation of the drug could not be demonstrated in this mutant. Protein synthesis on the ribosomes from the mutant was insensitive to streptomycin. These results suggest that ribosomal resistance is the reason for streptomycin resistance in Leptospira biflexa.