Reaction catalyzed by sphingolipid C9-methyltransferase (2.1.1.317)
+
=
+
S-adenosyl-L-methionine
+
a (4E,8E)-sphinga-4,8-dienine ceramide
=
S-adenosyl-L-homocysteine
+
a 9-methyl-(4E,8E)-sphinga-4,8-dienine ceramide