TABLE 1.

Relative activities of Arg-47 mutants compared to wild type PTEN acting on different PI(3)P substrate systems

The specific activities in nanomoles/mg min of wild type PTEN toward each substrate, determined at room temperature, are 14.2 ± 0.4 (diC₈PI(3)P), 45 ± 4 (diC₈PI(3,4)P₂), 11.5 ± 0.7 (diC₁₆PI(3)P/Triton X-100), 0.27 ± 0.03 (diC₁₆PI(3)P/POPC), and 0.59 ± 0.02 (DOPI(3,4)P₂/POPC). Mutants activities were measured in duplicate with errors <20% of the tabulated value.

	diC8PI(3)P 0.5 mm	diC8PI(3,4)P2 0.1 mm	diC16PI(3)P/ Triton X-100 (1:4)a	diC16PI(3)P/ POPC (1:9)b	DOPI(3,4)P2/POPC (1:19)c
R47G	0.040	0.019	0.049	0.063	0.23
R47W	0.010	–d	0.015	0.052	–
R47L	0.014	–	0.041	0.24	–
R47K	0.006	0.12	0.018	0.28	0.29

^a The concentration of diC₁₆PI(3)P was 0.1 mm.

^b The total phospholipid concentration was 1 mm.

^c The DOPI(3,4)P₂ concentration was 0.1 mm.

^d – indicates not determined.