ID 1.14.19.38 DE acyl-lipid Delta(6)-acetylenase. CA (1) (6Z,9Z,12Z)-octadecatrienoyl-containing glycerolipid + 2 Fe(II)- CA [cytochrome b5] + 2 H(+) + O2 = a (9Z,12Z)-octadeca-9,12-dien-6-ynoyl- CA containing glycerolipid + 2 Fe(III)-[cytochrome b5] + 2 H2O. CA (2) (6Z,9Z,12Z,15Z)-octadecatetraenoyl-containing glycerolipid + CA 2 Fe(II)-[cytochrome b5] + 2 H(+) + O2 = a (9Z,12Z,15Z)-octadeca-9,12,15- CA trien-6-ynoyl-containing glycerolipid + 2 Fe(III)-[cytochrome b5] + CA 2 H2O. CC -!- The enzyme, characterized from the moss Ceratodon purpureus, converts CC the double bond at position 6 of gamma-linolenate and stearidonate CC into a triple bond. CC -!- The product of the latter, dicranin, is the main fatty acid found in CC C. purpureus. CC -!- The enzyme contains a cytochrome b5 domain that acts as the direct CC electron donor to the desaturase active site. CC -!- The enzyme also has the activity of EC 1.14.19.47. DR Q9LEN0, ACET6_CERPU; //