Accepted name: hydroxysqualene dehydroxylase
Reaction: squalene + FAD + H2O = hydroxysqualene + FADH2
Glossary: hydroxysqualene = (6E,10E,12R,14E,18E)-2,6,10,15,19,23-hexamethyltetracosa-2,6,10,14,18,22-hexaen-12-ol
Other name(s): hpnE (gene name)
Systematic name: squalene:FAD oxidoreductase (hydroxylating)
Comments: This enzyme, isolated from the bacteria Rhodopseudomonas palustris and Zymomonas mobilis, participates, along with EC, presqualene diphosphate synthase, and EC, hydroxysqualene synthase, in the conversion of all-trans-farnesyl diphosphate to squalene. Eukaryotes achieve the same goal in a single step, catalysed by EC, squalene synthase.
1.  Pan, J.J., Solbiati, J.O., Ramamoorthy, G., Hillerich, B.S., Seidel, R.D., Cronan, J.E., Almo, S.C. and Poulter, C.D. Biosynthesis of squalene from farnesyl diphosphate in bacteria: three steps catalyzed by three enzymes. ACS Cent. Sci. 1 (2015) 77–82. [PMID: 26258173]
[EC created 2016]