Table 1.

Effect of buffers and chelating agents on the inactivation of AP by T

Agent added*	[Agent], mM	AP activity, %
		In the absence of T	In the presence of T
None	0	100	>80
Tris	500	90.8	11.5
Citrate	0.5	94	40.4
GSH	0.5	94.8	77.2

^*AP, 0.5 μM, was incubated with T, 1 μM, in 10 mM Tris·HCl, pH 8.0, in the presence of Tris, sodium citrate, or GSH. Aliquots were taken after 2 hr and assayed spectrophotometrically for enzymatic activity at 20°C.