Preparation of 3′-Phosphoadenosine 5′-Phospho35S-sulfate Using ATP Sulfurylase and APS Kinase fromBacillus stearothermophilus: 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.