Table 1.
Expression of CA activity
| Construct | CA activity, enzyme units/mg cell protein
|
|
|---|---|---|
| − acetazolamide | + acetazolamide (1 μM) | |
| pCXN (vector only) | 0.25* | 0.0 |
| pCXN-HCAXII-5 | 2.25 | 0.3 |
| pCXN-HCAXII-7 | 2.15 | 0.2 |
| pCXN-bovine CA IV | 12.3 | 0.25 |
*The low activity seen in vector-only transfections is acetazolamide-sensitive and attributable to a low level of CA II expression in COS cells (A. Waheed, personal communication). Inhibition of CA activity was 87% and 91% for CA XII clones 5 and 7, respectively, and 98% for CA IV.