DOI: 10.1128/AAC.45.4.1104-1108.2001
Article Figures & Data
Tables
- Table 1.
Sources and characteristics of trimethoprim-resistant and -susceptible S. pneumoniae isolates
Isolate Sourcea Serotypeb MIC (mg/liter) Sulfamethoxazole Trimethoprim Pn94/720c CSF 23F 512 256 Pn93/1293d Blood culture 6B 512 256 Pn93/1802e Blood culture 9V 256 256 P48 Unknown ND 1,024 256 R12 Sputum ND 256 512 Pn93/1791 Blood culture 19F 16 4 Pn93/917 CSF 9V 32 8 Pn93/908 CSF 14 32 4 Pn94/258 Blood culture 23F 32 4 CP1015 — 64 4 ATCC 49619 — 64 4 - Table 2.
Amino acid differences in DHFR sequences of trimethoprim-resistant and -susceptible isolates
Isolate Amino acid at positiona: MIC (mg/liter) 14* 16 20* 26 53 60* 70* 74* 78 81* 83 86 91* 92* 94* 100* 111 120 133 135* 147 149* 164 ATCC 49619 E V E H M K P I A Q V V Q D E I P H E L F A K 4 CP1015 — L — — — — — — — — — — — — — — — — — — — — — 4 Pn93/1791 — — — — — — — — — — — I — — — — — — K — — — — 4 Pn93/917 — — D — — — — — — — — — — A — — A — — — — — — 8 Pn93/908 — — D — — — — — — — — — — A — — A — — — — — — 4 Pn94/258 — — — — — — — — — — — — — A — — A — — — — — — 4 Pn93/720 D — D — — — S L — H — — H A D L — — — F S T E 256 Pn93/1293 — — D Y — — S — T Y — — — S D L — — — F S S — 256 Pn93/1802 — — D Y I Q S — T — — — — A — L — Q — F S T — 256 P48 — — D — — — S — — H I — — A D L — Q — F S T — 256 R12 — — D Y I Q S — T — — — — A — L — Q — F S T — 512 ↵a *, positions at which amino acids are altered in all trimethoprim-resistant isolates reported by Hartman et al. (37th ICAAC), Adrian and Klugman (1), Pikis et al. (15), and the present study; —, amino acid is the same as in ATCC 49619.
- Table 3.
Amino acid sequence changes and DHFR characteristics of selected CP1015 transformants
Isolate Amino acid at positiona: MIC (mg/liter) IC50(μM) Km(μM)b Specificity constantc 14 16 20 26 53* 60 70 74 78 81 91 92 94 100*† 120 135 147 149 DHF NADPH ATCC 49619 V 4 0.05 3.9 (0.83) 17.8 (4.4) 0.024 CP1015 E L E H M K P I A Q Q D E I H L F A 4 0.09 3.1 (0.48) 18.2 (3.2) 0.014 720/T1 D V D S L H H A D L F S T 512 2.9 9.2 (3.3) 30.7 (7.9) 0.09 720/T2 V D S L H H A D L 256 1.4 12.6 (3.3) 21.9 (5.2) 0.04 1802/T1 V D Y I Q S T A L Q F S T 512 13.7 14.3 (2.3) 29.0 (4.4) 0.026 1802/T2 V D Y I Q S T A L 512 10.1 24.1 (8.6) 52.7 (23.7) 0.007 R12/T1 T A L Q F S T 256 2.1 15.2 (2.8) 20.3 (4.7) 0.016 R12/T2 A L 128 4.2 27.7 (9.7) 35.1 (11.4) 0.0063
