Reaction: prenyl diphosphate + 5 3-methylbut-3-en-1-yl diphosphate = all-trans-hexaprenyl diphosphate + 5 diphosphate
Glossary: prenyl diphosphate = dimethylallyl diphosphate
3-methylbut-3-en-1-yl diphosphate = isopentenyl diphosphate
Other name(s): HexPPS
Systematic name: prenyl-diphosphate:3-methylbut-3-en-1-yl-diphosphate transferase (adding 5 units of 3-methylbut-3-en-1-yl)
Comments: This activity has been characterized from a number of fungal bifunctional enzymes. Following the formation of hexaprenyl diphosphate, a different domain in the enzymes catalyses its cyclization into a triterpene (see EC 4.2.3.221, macrophomene synthase and EC 4.2.3.220, talaropentaene synthase). cf. EC 2.5.1.82, hexaprenyl diphosphate synthase [geranylgeranyl-diphosphate specific].
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Tao, H., Lauterbach, L., Bian, G., Chen, R., Hou, A., Mori, T., Cheng, S., Hu, B., Lu, L., Mu, X., Li, M., Adachi, N., Kawasaki, M., Moriya, T., Senda, T., Wang, X., Deng, Z., Abe, I., Dickschat, J.S. and Liu, T. Discovery of non-squalene triterpenes. Nature 606 (2022) 414-419. [PMID: 35650436]