Proposed to provide activated sulfate for transfer to Nod factor. ATP sulfurylase may be the GTPase, regulating ATP sulfurylase activity (By similarity). APS kinase catalyzes the synthesis of activated sulfate. ATP + H(+) + sulfate = adenosine 5'-phosphosulfate + diphosphate adenosine 5'-phosphosulfate + ATP = 3'-phosphoadenylyl sulfate + ADP + H(+) Sulfate-activating enzymes, NodP and NodQ, may be physically associated. In the C-terminal section; belongs to the APS kinase family. In the N-terminal section; belongs to the TRAFAC class translation factor GTPase superfamily. Classic translation factor GTPase family. CysN/NodQ subfamily.