Analytical methods
The optical density at 600 nm (OD600) was measured using
a spectrophotometer. ATP, APS, and PAPS were quantified by
high-performance liquid chromatography (HPLC). The analysis was
performed with an HPLC system equipped with an
polyamine
column (YMC-Pack PolyamineⅡ, 250 mm×4.6 mm) and 0.7 mM of
KH2PO4 as the mobile phase. The flow
rate of the mobile phase was 0.6 mL/min and oven temperature was
maintained at 30℃ throughout the operation with an UV detector at 254
nm. Meanwhile, the product APS and PAPS were also analyzed by ESI-MS and
the molecular weight was in accordance with that of standard.
More materials and methods are shown in Supporting Information.