TABLE 4.
Effects of various compounds on the ATPase activity of the M. jannaschii PAN and PAN(Δ1–73) proteins
| Effector | Concn (mM) | Relative activitya
|
|
|---|---|---|---|
| PAN | PAN(Δ1–73) | ||
| None | 100 ± 6 | 100 ± 5 | |
| EDTA | 10 | 8 ± 3 | UDd |
| SDS | 0.1 | 63 ± 5 | |
| 0.2 | 3 ± 4 | ||
| NEMb | 10 | UD | 15 ± 4 |
| 5 | 23 ± 1 | ||
| 1 | 81 ± 8 | ||
| PCMSc | 0.05 | UD | UD |
| NaN3 | 5 | 90 ± 2 | 74 ± 5 |
a
ATPase activity is expressed as a percentage of the control reaction with no added effector. The enzyme (2 μg per ml) was preincubated with or without the effector in 100 mM NaCl, 10 mM MgCl2, 25 mM TES (pH 8.0) at 21°C for 15 min before addition of 1 mM ATP and incubation at 80°C (PAN) or 65°C [PAN(Δ1–73)].
b
NEM, N-ethylmaleimide.
c
PCMS, p-chloromercuriphenyl-sulfonic acid.
d
UD, undetectable.