TABLE 2.

RNA depurinating activities and in vivo anti-HIV activities of wild-type and mutant PAPs

Mutant and RNA source	Purine release (pmol/μg of RNA/μmol of PAP)		IC50 (μg/ml) for inhibition of HIV-1 HTLV IIIB replication	Cytotoxicity (CC50 [μg/ml])
	Adenine	Guanine
FLP-WT
E. coli	76 ± 4	71 ± 3	2.9 ± 1.3	3.1 ± 1.9
HIV-1	36 ± 3	48 ± 3
FLP-102
E. coli	7 ± 2	7 ± 2	0.2 ± 0.0	>10
HIV-1	100 ± 7	207 ± 11
FLP-105
E. coli	17 ± 3	10 ± 4	0.7 ± 0.2	>10
HIV-1	86 ± 7	180 ± 10