O-phospho-L-serine + sulfite + H(+) <=> L-cysteate + phosphate
o-phospho-l-serine + sulfite + h(+) <=> l-cysteate + phosphate
O-phospho-L-serine + sulfite + H(+) <=> L-cysteate + phosphate
o-phospho-l-serine + sulfite + h(+) <=> l-cysteate + phosphate