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Table 1 Mutations detected in all strains analyzed

From: Sequence analysis for detection of first-line drug resistance in Mycobacterium tuberculosis strains from a high-incidence setting

Gene Mutation Strains phenotypically susceptible to INH (n=) Strains phenotypically resistant to INH (n=)
katG wild type 65 4(1)
  Ala291Thr (gct/act); Ser315Thr (agc/acc)   1
  Trp300Cys (tgg/tgc)   1
  Thr302Arg (acg/agg)   1
  Ser315Thr (acg/acc)   21
  Asp329 (gac/ggac frameshift)   1
  Arg463Leu (cgg/ctg)(2)   2
  Gln471Arg (cag/cgg); Ser315Thr (agc/acc)   1
  Strains phenotypically susceptible to RIF (n=) Strains phenotypically resistant to RIF (n=)
rpoB wild type 76  
  Thr481Ala (acc/gcc)(3)   1
  Leu511Pro (ctg/ccg)(4) 1  
  Asp516Tyr (gac/tac)(4) 3  
  His526Tyr (cac/tac)   3
  His526Arg (cac/cgc)   3
  Ser531Leu (tcg/ttg)   8
  Leu533Pro (ctg/ccg)(4) 1 1
  Strains phenotypically susceptible to SM (n=) Strains phenotypically resistant to SM (n=)
rpsL wild type 56 21
  Lys43Arg (aag/agg)   11
  Lys88Arg (aag/agg) 1 8
gidB wild type 26 (2 with mutations in rrs/rpsL) 15 (10 with mutations in rpsL)
  Leu16Arg (ctt/cgt) 4 2
  Leu16Arg (ctt/cgt); Gln127stop (caa/taa); Ala161Ala (gcc/gcg) 1  
  Leu16Arg (ctt/cgt); Ala161Ala (gcc/gcg) 2 1 (Lys43Arg in rpsL)
  Leu16Arg (ctt/cgt); Ala200Glu (gcg/gag)   2
  Leu16Arg (ctt/cgt); Ala205Ala (gca/gcg)   1 (Lys43Arg in rpsL)
  Gly34Ala (ggg/gcg)   1
  Pro38 (ccc/cc frameshift)   1 (Lys88Arg in rpsL)
  Val65Gly (gtc/ggc)   1
  Gly69Asp (ggt/gat) 1 2
  Gly71Arg (gga/aga)   1
  Val88Ala (gta/gca)   1
  Leu91Pro (cta/cca)   1
  Gly92Asp (gaa/gac) 1  
  Gly92Asp (gaa/gac); Ala205Ala (gca/gcg)   3 (Lys43Arg in rpsL)
  Ser100Phe (tct/ttt)   1
  Val110Val (gtg/gtt); Ala205Ala (gca/gcg) 4  
  Ala138Val (gcg/gtg)   2
  Ala200Glu (gcg/gag) + Ala205Ala (gca/gcg)   1
  Ala205Ala (gca/gcg) 18 4 (3 with mutations in rpsL)
  Strains phenotypically susceptible to EMB (n=) Strains phenotypically resistant to EMB (n=)
embB wild type 82 4(5)
  Met306Ile (atg/ata)   6
  Met306Val (atg/gtg)   1
  Trp332Arg (tgg/cgg)   1
  Gln497Lys (cag/aag)(3)   1
  Gln1002Arg (cag/cgc)(3)   2
  Strains phenotypically susceptible to PZA (n=) Strains phenotypically resistant to PZA (n=)
pncA wild type 84 3
  −11 (a/g)   1
  Ile5 (atc/atcc frameshift)   1
  Thr47Ala (acc/gcc) 2  
  Tyr64 (tat/tata frameshift)   1
  Lys96Glu (aag/gag) 1  
  Gln141 (cag/cag acggcgccag (insertion of 10 bp → frameshift)   1
  Ala146Glu (gcg/gag)   1
  Gly162Asp (ggt/gat)   1
  Leu172Pro (ctg/ccg)   1
  1. Sequence analysis and drug susceptibility testing has been repeated for all strains showing discrepant results.
  2. Abbreviations: INH, isoniazid; RIF, rifampin; SM, streptomycin; EMB, ethambutol; PZA, pyrazinamide.
  3. (1)Those strains were additionally sequenced in the promoter region of inhA and ahpC. Two of them carried a mutation in inhA at position −15 (C → T) and one in ahpC at −57 (C → T).
  4. (2)Arg463Leu is a phylogenetic SNP [23] and was excluded for further analysis.
  5. (3)These mutations were identified by sequence analysis of the complete gene.
  6. (4)These mutations confer low-level RIF resistance.
  7. (5)These strains were sequenced in the complete embCAB operon. One strain carried a mutation in embC [Val981Leu (gtg/ctg)].