• A new assay for ATP sulfurylase (ATP:sulfate adenylyltransferase, EC 2.7.7.4) has been devised, the key feature of which is the quantitative precipitation of the unreacted substrate as Na 2SO 4, in ethanol:water (5:1), leaving the product adenosine 5′-phosphosulfate (APS) in solution with an 80% yield. (naver.com)