title: Absolute Configuration of Hydroxysqualene. An Intermediate in Bacterial Hopanoid Biosynthesis.
abstract: Squalene (SQ) is a key intermediate in hopanoid biosynthesis. Many bacteria synthesize SQ from farnesyl diphosphate (FPP) in three steps: FPP to (1R,2R,3R)-presqualene diphosphate (PSPP), (1R,2R,3R)-PSPP to hydroxysqualene (HSQ), and HSQ to SQ. Chemical, biochemical, and spectroscopic methods were used to establish that HSQ synthase synthesizes (S)-HSQ. In contrast, eukaryotic squalene synthase catalyzes solvolysis of (1R,2R,3R)-PSPP to give (R)-HSQ. The bacterial enzyme that reduces HSQ to SQ does not accept (R)-HSQ as a substrate.
authors.affiliation: Department of Chemistry, University of Utah , 315 South 1400 East, Salt Lake City, Utah 84112, United States.
authors.forename: Jian-Jung
authors.initials: JJ
authors.lastname: Pan
authors.affiliation: Department of Chemistry, University of Utah , 315 South 1400 East, Salt Lake City, Utah 84112, United States.
authors.forename: Gurusankar
authors.initials: G
authors.lastname: Ramamoorthy
authors.affiliation: Department of Chemistry, University of Utah , 315 South 1400 East, Salt Lake City, Utah 84112, United States.
authors.forename: C Dale
authors.initials: CD
authors.lastname: Poulter
mesh_terms: D002384:Catalysis; D013186:Farnesyl-Diphosphate Farnesyltransferase / Q000378:metabolism; D050155:Lipogenesis; D015394:Molecular Structure; D011106:Polyisoprenyl Phosphates; D012717:Sesquiterpenes; D013185:Squalene / Q000031:analogs & derivatives* / Q000737:chemistry; D013237:Stereoisomerism; D014315:Triterpenes / Q000737:chemistry
chemical_list: D011106:Polyisoprenyl Phosphates; D012717:Sesquiterpenes; D014315:Triterpenes; C000608370:hydroxysqualene; C017672:presqualene pyrophosphate; C004808:farnesyl pyrophosphate; D013185:Squalene; D013186:Farnesyl-Diphosphate Farnesyltransferase