Table 1. Specific activities of human SULT1A3 with tyrosine isomers and derivatives as substrates.

Results are means±S.D. for three determinations.

Substrate	Specific activity (nmol/min per mg of protein)
L-Nitrotyrosine	2.11±0.07
L-p-Tyrosine	0.01±0.01
DL-m-Tyrosine	0.85±0.01
L-Dopa	2.06±0.04
Dopamine	15.92±0.11