Reaction catalyzed by squalene methyltransferase (2.1.1.262)
2
+
=
2
+
2 S-adenosyl-L-methionine
+
squalene
=
2 S-adenosyl-L-homocysteine
+
3,22-dimethyl-1,2,23,24-tetradehydro-2,3,22,23-tetrahydrosqualene
