Substrate | Vmax | Km | kcat/Km |
---|---|---|---|
nmol min -1 mg -1 | mM | min -1 mM -1 | |
R-(+)-1-Naphthyl-1-ethanol | 23.2 ± 4.2 | 0.24 ± 0.15 | 3.3 |
S-(-)-1-Naphthyl-1-ethanol | —b | ||
R-(+)-2-Naphthyl-1-ethanol | 22.7 ± 1.3 | 0.25 ± 0.05 | 3.1 |
S-(-)-2-Naphthyl-1-ethanol | 20.9 ± 0.4 | 0.54 ± 0.25 | 1.3 |
↵ a Values for kcat were calculated using the relative molecular mass for a single subunit of ST2A3, 33,648 as calculated from the deduced amino acid sequence. Values for Vmax and Km are presented as the mean ± standard error and were determined by the substrate-dependent formation of PAP in the reaction as described under Materials and Methods.
↵ b No sulfation of ST2A3 was detected for the S-(-)-1-naphthyl-1-ethanol at concentrations of 0.2, 0.4, and 0.8 mM.