15-cis-4,4'-diapophytoene + diphosphate => presqualene diphosphate
15-cis-4,4'-diapophytoene + diphosphate => presqualene diphosphate
15-cis-4,4'-diapophytoene + diphosphate => presqualene diphosphate
15-cis-4,4'-diapophytoene + diphosphate => presqualene diphosphate