TABLE 1.

Macrolide-lincosamide-streptogramin B resistance in S. pneumoniae due to gene acquisition

Gene(s)Resistance phenotype(s)aPhenotype forb:Reference
14-M and 15-MK16-MLSBSASA+B
erm(B)MLSB (i)RSRr or Rr or RSS33
MLSB (c)RRRRRSS
erm(A)MLSB (c)RRRRRSS38
mef(A)MRSSSSSS39
erm(B) + mef(A)MLSB + MRNDRRRSS23
  • a c, constitutive; i, inducible.

  • b 14-M, 15-M, and 16-M, 14-, 15-, and 16-membered macrolides, respectively; K, ketolides; L, lincosamides; SB, streptogramin B; SA, streptogramin A; SA+B, streptogramin A and B; r, low-level resistance; R, high-level resistance; S, susceptibility; ND, not determined.