TABLE 1.

The NS3 helicase domain enhances NS3-4A protease activity The proteolysis data were determined by monitoring RET-S1 cleavage on a fluorescence spectrophotometer (see “Experimental Procedures”). The data shown were determined using proteins of the 1a genotype and is the average of three experiments. The error values represent standard deviation.

Protein	Km	Vmax	kcat	kcat/Km
	μm	pmol RET-S1 cleaved/s	pmol RET-S1 cleaved/s/pmol enzyme	pmol RET-S1 cleaved/s/pmol enzyme/μm substrate
NS3/4A	10.0 ± 3.0	17 ± 2	3.15 ± 0.30	0.315
NS3 + NS4A	3.0 ± 1.0	0.50 ± 0.05	0.09 ± 0.01	0.030
NS3 protease domain + NS4A	4.0 ± 1.2	0.11 ± 0.01	0.020 ± 0.002	0.005