TABLE 1.
Scheme for purification of the toxin from A. actinomycetemcomitans Y4a
| Purification step | Protein (mg) | Total activity (U) | Sp act (U/mg) | Purification (fold) | Recovery (%) |
|---|---|---|---|---|---|
| Culture supernatant | 330.01 | 17,161 | 52 | 1 | 100 |
| Ammonium sulfate precipitation | 60.00 | 15,600 | 260 | 5 | 91 |
| POROS HQ/M column | 17.27 | 15,267 | 884 | 17 | 89 |
| Polymyxin B matrix | 15.35 | 13,892 | 905 | 17 | 81 |
| Mono-Q HR5/5 column | 0.33 | 7,413 | 22,464 | 432 | 43 |
a
Cytotoxicity (in units per milliliter) was expressed as the reciprocal of the highest dilution producing 50% inhibition by the MTT viability assay. Culture supernatant (5 liters) was used as the starting material.