Reaction: geranylgeranyl diphosphate + 2 isopentenyl diphosphate = 2 diphosphate + all-trans-hexaprenyl diphosphate
For diagram of reaction, click here
Other name(s): HexPS(ambiguous); (all-E) hexaprenyl diphosphate synthase; (all-trans) hexaprenyl diphosphate synthase; hexaprenyl pyrophosphate synthase (ambiguous); HexPPs (ambiguous); hexaprenyl diphosphate synthase (ambiguous)
Systematic name: geranylgeranyl-diphosphate:isopentenyl-diphosphate transferase (adding 2 isopentenyl units)
Comments: The enzyme prefers geranylgeranyl diphosphate to farnesyl diphosphate as an allylic substrate and does not show activity for geranyl diphosphate and dimethylallyl diphosphate. Requires Mg2+ [1].
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:
References:
1. Hemmi, H., Ikejiri, S., Yamashita, S. and Nishino, T. Novel medium-chain prenyl diphosphate synthase from the thermoacidophilic archaeon Sulfolobus solfataricus. J. Bacteriol. 184 (2002) 615-620. [PMID: 11790729]
2. Hemmi, H., Noike, M., Nakayama, T. and Nishino, T. Change of product specificity of hexaprenyl diphosphate synthase from Sulfolobus solfataricus by introducing mimetic mutations. Biochem. Biophys. Res. Commun. 297 (2002) 1096-1101. [PMID: 12372398]
3. Sun, H.Y., Ko, T.P., Kuo, C.J., Guo, R.T., Chou, C.C., Liang, P.H. and Wang, A.H. Homodimeric hexaprenyl pyrophosphate synthase from the thermoacidophilic crenarchaeon Sulfolobus solfataricus displays asymmetric subunit structures. J. Bacteriol. 187 (2005) 8137-8148. [PMID: 16291686]