Table 1.
Antifungal susceptibility testing of caspofungin, FK506, geldanamycin, and three triazoles against the wild-type AF293 and various clinical and laboratory A. fumigatus resistant strains
| Strain [amino acid substitution]a (reference) | MIC (μg/ml)b |
MEC (μg/ml)c |
||||
|---|---|---|---|---|---|---|
| ITZ | VCZ | POS | CSP | FK506 | GDA | |
| AF293 [wild type] | 0.25 | 0.25 | 0.25 | 0.5 | 0.016 | 4 |
| akuBKU80 (24)d | 0.25 | 0.25 | 0.25 | 0.5 | 0.032 | 4 |
| F16134 [M220K] (2) | >8 | 4 | >8 | 0.5 | 0.016 | 4 |
| F6919 [M220K] (2) | >8 | 2 | 2 | 1 | 0.016 | 4 |
| F14532 [M220T] (2) | >8 | 1 | 0.5 | 1 | 0.032 | 4 |
| F14946 [G138C] (2) | >8 | >8 | >8 | 0.5 | 0.064 | 5 |
| F12760 [G138C] (2) | >8 | 0.125 | 8 | 1 | 0.032 | 5 |
| F7075 [G54E] (2) | >8 | 1 | >8 | 1 | 0.032 | 5 |
| F12636 [G54E] (2) | >8 | 0.125 | 1 | 1 | 0.016 | 4 |
| F14403 [G54R] (2) | >8 | 0.5 | >8 | 0.5 | 0.016 | 4 |
| F16216 [L98H+TR] (2) | >8 | 8 | 2 | 1 | 0.016 | 4 |
| F12776 [Y431C] (2) | >8 | 4 | 1 | 1 | 0.1 | 5 |
| F13747 [G434C] (2) | >8 | 4 | 1 | 1 | 0.032 | 5 |
| VO44-58 [unknown] | >8 | 4 | 0.5 | 1 | 0.032 | 5 |
| EMFR-S678P [S678P] (10) | 0.25 | 0.25 | 0.25 | >16 | 0.032 | 5 |
The amino acid substitution refers to the gene cyp51A for azole-resistant strains and the gene fks1p for the echinocandin-resistant strain.
MICs are as reported from the Regional Mycology Laboratory Manchester (RMLM) (2) except for the MICs of AF293, akuBKU80, and EMFR-S678P (this study). ITZ, itraconazole; VCZ, voriconazole; POS, posaconazole.
MEC values as assessed in this study (means of triplicates). Of note, the cutoff for the MIC (>90% growth inhibition) was not reached for caspofungin, FK506, and geldanamycin. CSP, caspofungin; GDA, geldanamycin.
akuBKU80 is the reference (genetic background) strain for EMFR-S678P.