Preparation of 3′-Phosphoadenosine 5′-Phospho³⁵S-sulfate Using ATP Sulfurylase and APS Kinase from<i>Bacillus stearothermophilus</i>: Enzymatic Synthesis and Purification

Abstract

Radioactive PAPS was synthesized with a predetermined specific activity using enzymes purified from Bacillus stearothermophilus. The reaction system, incorporating 1.5mCi of 35S-H2SO4 and 500 nmol of ATP, produced 582 μCi of 35S-PAPS. The synthesized 35S-PAPS was purified by ECTEOLA cellulose chromatography, followed by desalting with DOWEX 50W-X8. The final yield was 206 μmol of 35S-PAPS with a radioactivity of 411 μCi.