title: Comparison of the biological properties of several marine sponge-derived sesquiterpenoid quinones.
abstract: Eight naturally occurring marine-sponge derived sesquiterpenoid quinones were evaluated as potential inhibitors of pyruvate phosphate dikinase (PPDK), a C4 plant regulatory enzyme. Of these, the hydroxyquinones ilimaquinone, ethylsmenoquinone and smenoquinone inhibited PPDK activity with IC50's (reported with 95% confidence intervals) of 285.4 (256.4-317.7), 316.2 (279.2-358.1) and 556.0 (505.9-611.0) microM, respectively, as well as being phytotoxic to the C4 plant Digitaria ciliaris. The potential anti-inflammatory activity of these compounds, using bee venom phospholipase A2 (PLA2), was also evaluated. Ethylsmenoquinone, smenospongiarine, smenospongidine and ilimaquinone inhibited PLA2 activity (% inhibition of 73.2 +/- 4.8 at 269 microM, 61.5 +/- 6.1 at 242 microM, 41.0 +/- 0.6 at 224 microM and 36.4 +/- 8.2 at 279 microM, respectively). SAR analyses indicate that a hydroxyquinone functionality and a short, hydroxide/alkoxide side-chain atC-20 is preferred for inhibition of PPDK activity, and that a larger amine side-chain at C-20 is tolerated for PLA2 inhibitory activity.
authors.affiliation: Australian Institute of Marine Science, Townsville, Queensland, 4810, Australia. c.motti@aims.gov.au
authors.forename: Cherie A
authors.initials: CA
authors.lastname: Motti
authors.forename: Marie-Lise
authors.initials: ML
authors.lastname: Bourguet-Kondracki
authors.forename: Arlette
authors.initials: A
authors.lastname: Longeon
authors.forename: Jason R
authors.initials: JR
authors.lastname: Doyle
authors.forename: Lyndon E
authors.initials: LE
authors.lastname: Llewellyn
authors.forename: Dianne M
authors.initials: DM
authors.lastname: Tapiolas
authors.forename: Ping
authors.initials: P
authors.lastname: Yin
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D031746:Digitaria / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006540:Herbicides / Q000494:pharmacology; D006801:Humans; D008956:Models, Chemical; D011161:Porifera / Q000737:chemistry*; D011809:Quinones / Q000737:chemistry / Q000378:metabolism*; D012717:Sesquiterpenes / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000893:Anti-Inflammatory Agents; D006540:Herbicides; D011809:Quinones; D012717:Sesquiterpenes