TABLE 2.
Phenotypic characteristics and changes in RpoB among the most prevalent RIF-resistant pneumococcal clones
PFGEa | Isolate | Serotype | Site | Yr | Originb | Resistance patternc | Nucleotide polymorphisms at rpoBd | Amino acid changes at RpoBe |
---|---|---|---|---|---|---|---|---|
Spain23F-1 | Rif-7 | 23F | HD | 1991 | Sputum | PTCSxTR | A516, V520, Q535, G551 | D489N, R501H |
Rif-14 | 23F | HD | 1993 | Sputum | PTCSxTR | A516, V520, Q535, G551 | H499N | |
Rif-22 | 23F | HD | 1994 | Blood | PTCSxTR | A516, V520, Q535, G551 | H499N | |
Rif-34 | 23F | HGM | 1996 | Blood | PTCEClSxTR | A516, V520, Q535, G551 | M488I, H499Y | |
Rif-35 | 23F | HGM | 1996 | Blood | PTCEClSxTR | A516, V520, Q535, G551 | M488I, H499Y | |
Rif-36 | 23F | HGM | 1996 | Blood | PTCEClSxTR | A516, V520, Q535, G551 | M488I, H499Y | |
Rif-38 | 23F | HGM | 1996 | Blood | PTCEClSxTR | A516, V520, Q535, G551 | M488I, H499Y | |
Rif-39 | 23F | HGM | 1996 | Pus | PTCEClSxTR | A516, V520, Q535, G551 | M488I, H499Y | |
Rif-63 | 23F | HD | 2001 | Eye | PTCEClSxTR | A516, V520, Q535, G551 | L506S | |
Rif-75 | 23F | HUB | 1995 | Sputum | PTEClSxTR | A516, V520, Q535, G551, S498 | H499N | |
Rif-76 | 23F | HUB | 1997 | Sputum | PTCSxTR | A516, V520, Q535, G551 | H499Y | |
Spain6B-2 | Rif-40 | 6B | HD | 1996 | Sputum | PTCR | A516, V520, Q535, G551 | H499Y |
Rif-42 | 6B | HGM | 1997 | BAL | PTEClSxTR | I468, Q535 | Q150R | |
Rif-18 | 6B | HD | 1994 | Sputum | PTEClR | I468, Q535 | D489G, L506V | |
Rif-19 | 6B | HD | 1994 | Blood | PTEClR | I468, Q535 | D489G, L506V | |
Rif-30 | 6B | HD | 1995 | Blood | PTEClR | I468, Q535 | D489G, L506V | |
Rif-17 | 6B | HUB | 1994 | Sputum | PTCEClSxTR | I468, Q535 | D489N, P537S | |
Rif-23 | 6B | HUB | 1995 | Sputum | PTCEClSxTR | I468, Q535 | H499Y | |
Rif-53 | 6B | HD | 1999 | Sputum | PTCEClSxTR | I468, Q535 | H499Y | |
Rif-13 | 6B | HCA | 1993 | BPS | PTCSxTR | Y589F, I608V, I624V, N669D, Q671K, H499N | ||
Spain9V-3 | Rif-55 | 14f | HCA | 2000 | Pleural | PSxTR | I468, Q535 | D489V |
Rif-1 | 9V | HD | 1990 | Sputum | PSxTR | I468, Q535 | H499Y | |
Spain14-5 | Rif-15 | 14 | HD | 1993 | Sputum | PTCEClSxTR | Y589F, H499N | |
Rif-16 | 14 | HD | 1993 | Sputum | PTCEClSxTR | Y589F, H499N | ||
Clone Cg | Rif-2 | 19F | HUB | 1991 | Sputum | PTSxTR | A474, V520, Q535 | S481P, H499Y |
Rif-3 | 19F | HUB | 1991 | Sputum | PTSxTR | A474, V520, Q535 | D489V | |
Rif-12 | 19F | HD | 1999 | Eye | PTCEClSxTR | A474, V520, Q535 | H499Y | |
Rif-28 | 19F | HUB | 1995 | Sputum | PCSxTR | A474, V520, Q535 | H499N | |
Rif-37 | 19F | HGM | 1996 | Sputum | PTEClSxTR | A474, V520, Q535 | H499N | |
Rif-31 | 19F | HD | 1995 | Blood | PTCSxTR | Y589F, D489V |
PFGE SmaI patterns.
BAL, bronchoalveolar wash specimen; BPS, bronchial protected catheter brush specimen.
P, resistant to penicillin (MIC, 0.12 to 4 μg/ml); T, resistant to tetracycline (MIC, ≥4 μg/ml); C, resistant to chloramphenicol (MIC, ≥8 μg/ml); E, resistant to erythromycin (MIC, ≥0.5 μg/ml); Cl, resistant to clindamycin (MIC, ≥0.5 μg/ml); SxT, resistant to trimethropin-sulfamethoxazole (MICs, ≥4/76 μg/ml); R, resistant to RIF (MIC, ≥4 μg/ml).
The RpoB regions sequenced were L42 to V175 and Q464 to T700. Nucleotide polymorphisms are indicated by the residue number; the changes observed were I468 (ATT instead ATC), A474 (GCG instead GCA), A516 (GCT instead GCC), V520 (GTA instead GTG), Q535 (GAG instead GAA), G551 (GGT instead GGA), and S498 (TCA instead TCT).
Residue changes involved in RIF resistance are showed in boldface, and double underlining indicates that the residue is located in a gene with a mosaic structure.
Capsular switching.
C, PFGE type related to serotype 19F with MLST type 89.