TABLE 1.
Specific activities of bacterially or mammalian cell expressed ELMOD proteins as ARL2 GAPs
ARL2 was present at a concentration of 0.2 μm in the assay. The specific activity of each ELMOD preparation was obtained from titration curves that included at least eight concentrations between 0 and 4 μm GAP. The specific activity values were calculated from the average of at least three points, each performed in duplicate, within the linear region of the curve obtained in two experiments using different preparations of each GAP. Variations within duplicates and between experiments were less than 15%.
| Protein | SA |
|
|---|---|---|
| HEK | Escherichia coli | |
| nmol min−1 mg−1 | ||
| GST-ELMOD1 | 0.76 | NDa |
| GST-ELMOD2 | 30.0 | ND |
| GST-ELMOD3 | 0.03 | ND |
| TF-ELMOD1 | ND | 0.0003 |
| TF-ELMOD2 | ND | 0.007 |
| TF-ELMOD3 | ND | NAb |
| CL ELMOD2c | 22 | ND |
| BVN ELMOD2d | 23 | ND |
a ND, not determined.
b NA, not active, indicates no detectable difference between the ELMOD sample and buffer control in the GAP assay.
c CL, ELMOD2 that has had its GST tag cleaved with TEV protease.
d BVN ELMOD2, ELMOD2 purified from bovine testis.