TABLE 1.

Effect of inhibitors and activators on the proteolytic activity of Tpr

Activity was determined at 37 °C using Suc-LLVY-AMC as a substrate. Activity in buffer (50 mm Tris-HCl and 150 mm NaCl, pH 7.5, supplemented with 5 mm CaCl₂) alone was taken as 100%. Sample treated with 5 mm and 10 mm EDTA was saturated with Ca²⁺ (15 mm and 25 mm, respectively), and residual activity was determined.

Inhibitors and metal ions	Concentration	% of control
E-64	50 μm	0
	100 μm	0
Leupeptin	50 μm	0
	100 μm	0
Iodoacetic acid	1 mm	0
	5 mm	0
Pepstatin A	50 μm	73
	100 μm	60
Orthophenanthroline	50 μm	101
	100 μm	104
TLCK	50 μm	0
	100 μm	0
Pefabloc	50 μm	67
	100 μm	58
EDTA	5 mm	0
	10 mm	0
Ca2+	–	0
	10 μm	0
	100 μm	0
	0.5 mm	0
	1 mm	0
	2 mm	25
	3 mm	54
	5 mm	100
	7 mm	35
	10 mm	31
DTT	1 mm	109
l-Cysteine	1 mm	99