Table 4.
Ratios from β-LEAF assays to assess activity of tested antibiotics in context of β-lactamase resistance
| |
S. aureus
isolate |
|||||
|---|---|---|---|---|---|---|
| Antibiotic | #1 | #2* | #6 | #18 | #19 | #20 |
| Cefazolin |
0.11 |
0.55 |
0.08 |
0.13 |
0.12 |
0.36 |
| Cefoxitin |
0.11 |
0.64 |
0.09 |
0.12 |
0.12 |
0.30 |
| Cefepime | 0.68 | 0.44 | 0.80 | 0.58 | 0.47 | 0.66 |
Ratios were calculated as [Cleavage rate (β-LEAF + antibiotic)/Cleavage rate (β-LEAF alone)] using data depicted in Figure 3, for each antibiotic for the different bacteria tested, and rounded to two decimal points. Closer the value to ‘1’, more active an antibiotic predicted to be for the respective bacterial strain/isolate taking β-lactamase resistance into consideration.
NOTE: *For isolates that show low cleavage rates with β-LEAF (e.g. #2), there is negligible difference in values when antibiotics are included in the reaction, and the ratios may give exaggerated results. For such strains, the antibiotics may be considered active/usable.