TABLE 2.
Hydrolysis parameters for SHV-1 and SHV-11 β-lactamases for selected β-lactamsc
| Antibiotic | Wavelength | Δɛ(M−1cm−1) | SHV-1 J53R1010 (reference)a | SHV-11 (S. dysenteriae) |
|---|---|---|---|---|
| Benzylpenicillin | 232 | 800 | 100 | 100 |
| Ampicillin | 235 | 670 | 150 | 300 |
| Oxacillin | 260 | 400 | <0.1 | 96 |
| Cloxacillin | 260 | 140 | <0.1 | 45 |
| Carbenicillin | 235 | 830 | 20 | 45 |
| Nitrocefin | 482 | 15,000 | NDc | 150 |
| Cephaloridine | 255 | 9,000 | 50 | 35 |
| Cefazolin | 273 | 6,600 | 10 | 10 |
| Cefuroxime | 273 | 7,500 | <0.1 | 6 |
| Cefotaxime | 264 | 6,700 | <0.1 | 8 |
| Cefacetrile | 260 | 7,400 | 5 | 4 |
| Cefoperazone | 260 | 5,700 | ND | 4 |
| Cefaclor | 260 | 7,200 | 8 | 15 |
| Ceftizoxime | 255 | 5,000 | <0.1 | 18 |
| Ceftazidime | 260 | 8,600 | <0.1 | <0.1 |
| Cefsulodin | 265 | 5,800 | <0.1 | <0.1 |
| Cefoxitin | 265 | 7,380 | <0.1 | <0.1 |
| Imipenem | 297 | 9,000 | <0.1 | <0.1 |
a
SHV-1 J53R1010 was a gift from Antone A. Medeiros.
b
ND, not determined.
c
Results are the means of three determinations (standard deviation, ≤10%). Rates of hydrolysis (Vmax) of β-lactams are expressed relative to the rate of hydrolysis of benzylpenicillin, which was set at 100.