TABLE 2.

Summary of ATPase and RNA helicase activities of wild-type and mutant forms of HCV NS3 helicase

Mutant	Mutated sequencea	ATPase activity		Helicase activity
		kcat/Km (mM−1min−1)	% of wild-type activity	kcat/Km (mM−1min−1)	% of wild-type activity
Motif I
WT 5′-1175	AxxGxGKS	2,693.6	100	2,737.6	100
A204V	VxxGxGKS	2,491.7	93	1,966.1	72
K210Nc	AxxGxGNS	UDb	0	UD	0
Motif II
WT 5′-1175	DECH	2,693.6	100	2,737.6	100
D290N	NECH	UD	0	UD	0
E291A	DACH	2,104.5	78	2,212.7	81
E291Q	DQCH	UD	0	UD	0
C292A	DEAH	1,423.2	53	2,252.4	82
H293A	DECA	173.1	6	2,040.9	75
H293K	DECK	1,173.7	44	1,793.7	66
H293Q	DECQ	782.1	29	2,098.6	77
C292A/H293D	DEAD	UD	0	UD	0
C292A/H293D/Q460H	DEAD/HRxGRxGR	UD	0	UD	0
Motif III
WT 5′-1175	TAT	2,693.6	100	2,737.6	100
T322A	AAT	804.1	30	1,699.5	62
T324A	TAA	424.7	16	1,693.9	62
Motif VI
WT 5′-1175	QRxGRxGR	2,693.6	100	2,737.6	100
R461Q	QQxGRxGR	200.5	7	UD	0
Nucleic acid interaction
WT 5′-1175	V432/W501	2,693.6	100	2,737.6	100
V432A	A432	1,653.6	61	1,856.8	68
W501A	A501	2,140.5	79	UD	0
V432A + W501A	A432/A501	227.5	8	UD	0

^aMutated residues are in boldface. 

^bUD, undetectable. 

^cThe mutants that completely lose RNA helicase activity are K210N, D290N, E291Q, C292A/H293D, C292A/H293D/Q460H, R461Q, W501A, and V432A + W501A.