title: Circadian rhythm of anti-fungal prenylated chromene in leaves of Piper aduncum.
abstract: Leaves of Piper aduncum accumulate the anti-fungal chromenes methyl 2,2-dimethyl-2H-1-chromene-6-carboxylate (1) and methyl 2,2-dimethyl-8-(3'-methyl-2'-butenyl)-2H-1-chromene-6-carboxylate (2). The enzymatic formation of 2 from dimethylallyl diphosphate and 1 was investigated using cell-free extracts of the title plant. An HPLC assay for the prenylation reaction was developed and the enzyme activity measured in the protein extracts. The prenyltransferase that catalyses the transfer of the dimethylallyl group to C-2' of 1 was soluble and required dimethylallyl diphosphate as the prenyl donor. In the leaves, the biosynthesis of the prenylated chromene 2 was time-regulated and prenyltransferase activity depended upon circadian variation. Preliminary characterisation and purification experiments on the prenyltransferase from P. aduncum have been performed.
authors.affiliation: Instituto de Química, Universidade Estadual Paulista, UNESP, CP 355, Araraquara-SP, 14800-900, Brazil.
authors.forename: Andreia de A
authors.initials: Ade A
authors.lastname: Morandim
authors.forename: Débora Cristina B
authors.initials: DC
authors.lastname: Bergamo
authors.forename: Massuo Jorge
authors.initials: MJ
authors.lastname: Kato
authors.forename: Alberto José
authors.initials: AJ
authors.lastname: Cavalheiro
authors.forename: Vanderlan da S
authors.initials: Vda S
authors.lastname: Bolzani
authors.forename: Maysa
authors.initials: M
authors.lastname: Furlan
mesh_terms: D000935:Antifungal Agents / Q000378:metabolism; D001578:Benzopyrans / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D002940:Circadian Rhythm; D004122:Dimethylallyltranstransferase / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D031701:Piper / Q000201:enzymology / Q000378:metabolism*; D018515:Plant Leaves / Q000201:enzymology / Q000378:metabolism; D010946:Plants, Medicinal / Q000378:metabolism; D017368:Protein Prenylation / Q000502:physiology
chemical_list: D000935:Antifungal Agents; D001578:Benzopyrans; D004122:Dimethylallyltranstransferase