(9Z)-heptadecenoyl-CoA + 2 Fe(II)-[cytochrome b5] + O2 + 2 H(+) = (9Z,12Z)-heptadecadienoyl-CoA + 2 Fe(III)-[cytochrome b5] + 2 H2O
(9z)-heptadecenoyl-coa + 2 fe(ii)-[cytochrome b5] + o2 + 2 h(+) = (9z,12z)-heptadecadienoyl-coa + 2 fe(iii)-[cytochrome b5] + 2 h2o
(9Z)-heptadecenoyl-CoA + 2 Fe(II)-[cytochrome b5] + O2 + 2 H(+) = (9Z,12Z)-heptadecadienoyl-CoA + 2 Fe(III)-[cytochrome b5] + 2 H2O
(9z)-heptadecenoyl-coa + 2 fe(ii)-[cytochrome b5] + o2 + 2 h(+) = (9z,12z)-heptadecadienoyl-coa + 2 fe(iii)-[cytochrome b5] + 2 h2o