Table 2.

ITC determination of C32A Trx binding to different PAPR forms in absence or presence of saturating PAPS/PAP at 25 °C

Entry	PAPR form	Kd, μM	Fold > Kd
1	PAPR-S-SO3−	1.5 ± 0.3	—
2	PAPR-SH	∼110	73.3
3	Truncated PAPR	No binding	—
4	C239A PAPR + PAPS	6.3 ± 0.5	4.2
5	PAPR-S-SO3− + PAP	7.6 ± 0.7	5.0

Experiments performed in 50 mM bis-Tris propane buffer with 0.02% Brij-35 (pH 7.4). Data reported as average ± SD from n = 2 measurements.