TABLE 3.
Mutations in 23S rRNA and changes in ribosomal proteins L4 and L22 in macrolide-resistant pneumococcal strains
| Strain | Mutation in 23S rRNA genea | Change in protein L22b | Acquired macrolide resistance gene | Changes in protein L4b | Multilocus sequence typec | Serotype |
|---|---|---|---|---|---|---|
| NRZ 288 | A138G, T389C, A2060Gd (A2058G) | WTe | None | S20N, A197V | 392 | 17F |
| NRZ 796 | A138G, A682G, A2061Gd (A2059G) | WT | None | S20N | New type | 7F |
| PS 2938 | G211A, T389C, A2937Gf | WT | None | R95H | New type | 15A |
| PS 2909 | T389C | C117T | None | Multiple | 663 | 19F |
| PW 555 | A2937G,f G2939T,f C3096Tg | WT | None | WT | 62 | 11A |
| NRZ 462 | A138G, A376T, T389C, G2135T, G2939Af | WT | erm(B) | WT | 43 | 19F |
| NRZ 810 | A138G, T139C, T389C, A2939Gf | WT | mef(A) | WT | New type | 23F |
The nucleotide sequences of 23S rRNA are those of S. pneumoniae, and the corresponding Escherichia coli numbering is given in parentheses.
The positions of L4 and L22 are according to the sequence of S. pneumoniae R6 (GenBank accession number AF126059).
The following strains had the indicated multilocus sequence allele numbers: NRZ 288, 7-5-1-1-6-31-14; NRZ 796, 8-9-1-1-6-28-17; PS 2938, 10-13-14 variant-16-6-1-8; PS 2909, 7-13-8-6-6-6-99; PW 555, 2-5-29-12-16-3-14; NRZ 462, 1-10-4-1-9-3-8; NRZ 810, 15-29-4-21-30-1-8.
The mutation was seen in four of four alleles.
WT, wild type.
Mutations outside the 23S rRNA. The G2939A mutation is identical to the sequence of serotype 4 strain (tigr. org) but different from the sequence of S. pneumoniae R6. The mutations are found in the internal transcribed spacer between the 3′ end of the 23S rRNA and the 5′ start of the 5S rRNA, 35 and 37 bases, respectively, relative to the 3′ end of the 23S rRNA.
Mutation outside the 23S rRNA. The mutation is found in the internal transcribed spacer between the 3′ end of the 5S rRNA and the 5′ start of the t-RNA-valine 3; 94 bases relative to the 3′ end of the 23S rRNA.