Figure 4

Relative mobility of various sulfated small molecule products. To maximize the sensitivity of the detection, no cold PAPS was added into these reactions. Acceptor substrates are indicated on top of the autoradiogram. Lane 1 contained no acceptor substrate but 1 μg of rhSULT1A1. Lane 2, 3, 4 were labeled with 1 μg of rhSULT1A1, rhSULT1E1 and rhCHST4 respectively. All other lanes were labeled with 1 μg rhSULT2A1. Two product bands were observed in rhSULT1A1/dopamine reaction (lane 2) but not in rhSULT1E1/dopamine reaction (lane 3). Acceptor substrate inputs from lane 2 to 9 respectively were: 100 nmol dopamine, 100 nmol dopamine, 20 nmol GlcNAcMan, 10 nmol estradiol, 1 nmol DHEA, 10 nmol lithocholic acid, 10 nmol α-naphthol, and 100 nmol p-nitrophenol. The broken line indicates the position of the sulfated lithocholic acid. The distances that sulfated lithocholic acid and PAPS traveled are indicated as L _c and L _p , respectively. The ratio of L _c and L _p , 0.63, is the observed relative mobility for mono-sulfated lithocholic acid.