label: nitrite + 2 oxidized [2Fe-2S]-[ferredoxin] + H2O <=> nitrate + 2 reduced [2Fe-2S]-[ferredoxin] + 2 H(+)
label_lc: nitrite + 2 oxidized [2fe-2s]-[ferredoxin] + h2o <=> nitrate + 2 reduced [2fe-2s]-[ferredoxin] + 2 h(+)