activity assay for phenol sulfotransferase

[Dick Haugland]

Sulfation of phenols, in general, causes a shift of their absorption to
shorter wavelengths and, if they are fluorescent, quenches their
long-wavelength fluorescence.  Consequently p-nitrophenol is a
chromogenic substrate (Biochem Pharmacol 36, 1435 (1987); Drug Metabol
Disposition 17, 255 (1989)) and resorufin is a fluorometric substrate
that can also be measured by its absorption shift (Anal Biochem 197, 408
(1991)).  The latter may have higher sensitivity even in absortimetric
assay since its extinction coefficient is larger than that of
p-nitrophenol.  7-Hydroxy-4-methylcoumarin would likely work too.

Dick Haugland, President
Molecular Probes, Inc.
dick at probes.com