2-methyl-6-phytyl-1,4-benzene-1,4-diol + CO2 + diphosphate => phytyl diphosphate + homogentisate + H(+)
2-methyl-6-phytyl-1,4-benzene-1,4-diol + co2 + diphosphate => phytyl diphosphate + homogentisate + h(+)