label: an N-acylsphing-4-enine + 2 Fe(II)-[cytochrome b5] + O2 + 2 H(+) = a (4E,8E)-4-sphinga-4,8-dienine ceramide + 2 Fe(III)-[cytochrome b5] + 2 H2O
label_lc: an n-acylsphing-4-enine + 2 fe(ii)-[cytochrome b5] + o2 + 2 h(+) = a (4e,8e)-4-sphinga-4,8-dienine ceramide + 2 fe(iii)-[cytochrome b5] + 2 h2o