[thioredoxin]-disulfide + sulfite + adenosine 3',5'-bisphosphate + 2 H(+) <=> [thioredoxin]-dithiol + 3'-phosphoadenylyl sulfate
[thioredoxin]-disulfide + sulfite + adenosine 3',5'-bisphosphate + 2 h(+) <=> [thioredoxin]-dithiol + 3'-phosphoadenylyl sulfate