59163-53-0Relevant academic research and scientific papers
Pyrone polyketides synthesized by a type III polyketide synthase from Drosophyllum lusitanicum
Jindaprasert, Aphacha,Springob, Karin,Schmidt, Juergen,De-Eknamkul, Wanchai,Kutchan, Toni M.
experimental part, p. 3043 - 3053 (2009/04/11)
To isolate cDNAs involved in the biosynthesis of acetate-derived naphthoquinones in Drosophyllum lusitanicum, an expressed sequence tag analysis was performed. RNA from callus cultures was used to create a cDNA library from which 2004 expressed sequence tags were generated. One cDNA with similarity to known type III polyketide synthases was isolated as full-length sequence and termed DluHKS. The translated polypeptide sequence of DluHKS showed 51-67% identity with other plant type III PKSs. Recombinant DluHKS expressed in Escherichia coli accepted acetyl-coenzyme A (CoA) as starter and carried out sequential decarboxylative condensations with malonyl-CoA yielding α-pyrones from three to six acetate units. However, naphthalenes, the expected products, were not isolated. Since the main compound produced by DluHKS is a hexaketide α-pyrone, and the naphthoquinones in D. lusitanicum are composed of six acetate units, we propose that the enzyme provides the backbone of these secondary metabolites. An involvement of accessory proteins in this biosynthetic pathway is discussed.
ANTHRAQUINONE, ANTHRONE AND PHENYLPYRONE COMPONENTS OF ALOE NYERIENSIS VAR. KEDONGENSIS LEAF EXUDATE
Conner, John M.,Gray, Alexander I.,Reynolds, Tom,Waterman, Peter G.
, p. 2995 - 2998 (2007/10/02)
Key Word Index-Aloe nyeriensis var kedongensis; Liliaceae; leaf exudate; anthraquinones; nataloe-emodin; 2-O-β-D-glucopyranosylnataloe-emodin; anthrones; nataloin; 6-phenyl-4-methoxypyran-2-ones; aloenin; aloenin-2''-p-coumaroyl ester; aloenin aglycone; chemotaxonomy. The leaf exudate of Aloe nyeriensis var. kedongensis yielded six compounds which were identified on the basis of spectral data and inter-conversions as two groups of three allied compounds.These were (a) 4-methoxy-6-(2',4'-dihydroxy-6'-methylphenyl)-pyran-2-one, its 2'-O-β-D-glucopyranoside (aloenin) and the 2''-O-p-coumaroyl ester of aloenin, (b) the anthracene derivatives 1,2,8-trihydroxy-6-methylanthraquinone (nataloe-emodin), its 2-O-β-D-glucopyranosyl ester and the corresponding 10-C-β-D-glucopyranoside nataloin.
