Table 2.

Susceptibilities to isoniazid and rifampinaof the 14 M. bovis isolates analyzed in this study and mutations in genes involved in isoniazid and rifampin resistanceb

StrainSusceptibilityc to isoniazid (0.1 μg/ml)Isoniazid resistance-related mutationSusceptibilityc to rifampin (0.5 μg/ml)Rifampin resistance-related mutation
katGdinhAeoxyR-ahpCNucleotide substitutionCodonAmino acid mutation
416/0RE506K (GAG→AAG)209TWTRCAC→GAC526H→Y
868/30RE506K (GAG→AAG)209TWTRCAC→GAC526H→Y
621/2RL463R (CTG→CGG)WTWTS
621/4RL463R (CTG→CGG)WTWTS
621/6RL463R (CTG→CGG)WTWTS
621/10RS315T (AGC→ACC)WTWTS
621/16RWTWTWTRCAA→AAA513Q→K
621/17RWTWTWTRCAA→AAA513Q→K
1345/92SRCTG→CCG521L→P
1345/94SRCTG→CTT521L→P
1345/95SRCTG→CCG521L→P
1513/97RS315T (AGC→ACC)209TWTRCTG→CCG521L→P
1514/98SRCTG→CTT521L→P
1032/164SRCTG→CCG521L→P
  • a Determined by the BACTEC 460 TB radiometric method.

  • b Detected in 9 and 10 resistant M. bovis strains, respectively.

  • c R, resistant, S, susceptible.

  • d Amino acid mutation (nucleotide substitution). WT, wild type.

  • e Nucleotide substitution.