Molecular function

dimethylallyltransferase activity, geranyl diphosphate synthase

Catalysis of the reaction: dimethylallyl diphosphate + isopentenyl diphosphate = diphosphate + geranyl diphosphate.

(2E,6E)-farnesyl diphosphate synthetase activity, DMAPP:IPP-dimethylallyltransferase activity, dimethylallyl-diphosphate:isopentenyl-diphosphate dimethylallyltranstransferase activity, diprenyltransferase activity, geranyl pyrophosphate synthase activity, geranyl pyrophosphate synthetase activity, geranyl-diphosphate synthase activity, trans-farnesyl pyrophosphate synthetase activity

Note that this is the first step in the formation of farnesyl diphosphate. The second step is 'geranyltranstransferase activity ; GO:0004337'. Consider also annotating to the biological process term 'farnesyl diphosphate biosynthetic process ; GO:0045337'.