TABLE 1.
Effects of various compounds on GTFB-ΔN and GTFW-ΔN activitya
| Compound (1 mM) | GTFB-ΔN |
GTFW-ΔN |
||
|---|---|---|---|---|
| Hydrolysis activity (%) | Transferase activity (%) | Hydrolysis activity (%) | Transferase activity (%) | |
| None | 100 ± 4 | 405 ± 35 | 100 ± 8 | 180 ± 16 |
| EDTA | 75 ± 5 | 388 ± 51 | 90 ± 7 | 143 ± 14 |
| NaCl | 118 ± 12 | 404 ± 22 | 108 ± 11 | 171 ± 13 |
| CaCl2 | 111 ± 19 | 422 ± 65 | 121 ± 23 | 206 ± 33 |
| MnCl2 | 125 ± 15 | 425 ± 71 | 137 ± 16 | 223 ± 23 |
| MgCl2 | 94 ± 12 | 378 ± 5 | 108 ± 12 | 198 ± 18 |
| KCl | 86 ± 10 | 435 ± 6 | 109 ± 11 | 183 ± 10 |
| CuCl2 | 51 ± 5 | ND | 35 ± 7 | ND |
| FeCl2 | 50 ± 6 | 175 ± 42 | 64 ± 4 | 74 ± 15 |
| FeCl3 | 35 ± 5 | 85 ± 25 | 46 ± 6 | 32 ± 10 |
a
Incubations were performed at 40°C in a 25 mM NaAc buffer (pH 5.0) with amylose V (0.25%, wt/vol) as the substrate. The hydrolysis activity without additional compound was set at 100% (0.6 U/mg for GTFB-ΔN and 1.3 U/mg for GTFW-ΔN). ND, not detectable. The experiments were done in duplicate. The hydrolysis and transferase activities presented are means ± standard deviations.