TABLE 2.

Sulfation of Triclosan and Tolvaptan by Individual Human SULTs

SULT	pmol.min−1.mg cell lysate protein−1
	Triclosana	Tolvaptanb
1A1	15.2 ± 1.5	n.d.
1A2	193 ± 4.3	n.d.
1A3	182 ± 9.6	n.d.
1B1	199 ± 9.8	9.0 ± 0.3
1C2	38.6 ± 3.4	n.d.
1C3	22.9 ± 2.8	18.5 ± 0.5
1C4	210 ± 12.8	n.d.
1E1	190 ± 4.0	2.3 ± 0.1
2A1	26.7 ± 4.7	13.8 ± 0.6
2B1	34.1 ± 1.0	2.3 ± 0.2
4A1	20.8 ± 1.6	n.d.
6B1	8.9 ± 0.3	n.d.

^aSulfation assays were conducted in a 125 μl final reaction volume by incubating 0.25 mM [2,4-dichlorophenyl-¹⁴C(U)]triclosan (specific activity: 22.9 mCi/mmol) with 1.2 mg cell lysate proteins, 2 mM EDTA, 0.5 mM PAPS, and 100 mM sodium phosphate, pH 7.2, at 37°C for 2 h. Reactions were terminated by the addition of an equal volume of ice-cold methanol. Precipitated material was removed by centrifugation at 14,000 g at 4°C for 30 min and the supernatants were analyzed for tolvaptan and tolvaptan sulfate by a reversed-phase HPLC with radiochemical detection as previously described (Fang et al., 2014).

^bSulfation assays using 0.2 mM tolvaptan at 37°C for 1 h, as described in Materials and Methods. n.d.: not detected.