Role of aspartic acid residues D87 and D89 in APS kinase domain of human 3'-phosphoadenosine 5'-phosphosulfate synthase 1 and 2b: A commonality with phosphatases/kinases.

ABSTRACT: 3'-phosphoadenosine 5'-phosphosulfate (PAPS) is synthesized in two steps by PAPS synthase (PAPSS). PAPSS is comprised of ATP sulfurylase (ATPS) and APS kinase (APSK) domain activities. ATPS combines inorganic sulfate with α-phosphoryl of ATP to form adenosine 5'-phosphosulfate (APS) and PPi. In the second step APS is phosphorylated at 3'-OH using another mole of ATP to form PAPS and ADP catalyzed by APSK. The transfer of gamma-phosphoryl from ATP onto 3'-OH requires Mg₂ ⁺ and purported to involve residues D₈₇GD₈₉N. We report that mutation of either aspartic residue to alanine completely abolishes APSK activity in PAPS formation. PAPSS is an, unique enzyme that binds to four different nucleotides: ATP and APS on both ATPS and APSK domains and ADP

SUBMITTER: Venkatachalam KV 

PROVIDER: S-EPMC8528679 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature