TABLE 4.
Kinetic coefficients for outer membrane efflux of cephalosporins from the periplasm of Escherichia coli
| Compound | k (cm · s−1) | Concn range (μM)a | Sourceb |
|---|---|---|---|
| Nitrocefin | 3.2 × 10−5 | 0–3 | 3 |
| Cefamandole | 12.3 × 10−5 | 7–13 | 4 |
| Cephalothin | 4.9 × 10−5 | 20–100 | 5 |
| Cephaloridine | 2.7 × 10−5 | 50–250 | 6 |
a
Range of periplasmic concentrations over which the rate of efflux was proportional to the concentration.
b
The numbers refer to the figure numbers in the article presented by Nagano and Nikaido (32), from which the efflux coefficients, k, were calculated.