title: Relevant spatial scales of chemical variation in Aplysina aerophoba.
abstract: Understanding the scale at which natural products vary the most is critical because it sheds light on the type of factors that regulate their production. The sponge Aplysina aerophoba is a common Mediterranean sponge inhabiting shallow waters in the Mediterranean and its area of influence in Atlantic Ocean. This species contains large concentrations of brominated alkaloids (BAs) that play a number of ecological roles in nature. Our research investigates the ecological variation in BAs of A. aerophoba from a scale of hundred of meters to thousand kilometers. We used a nested design to sample sponges from two geographically distinct regions (Canary Islands and Mediterranean, over 2500 km), with two zones within each region (less than 50 km), two locations within each zone (less than 5 km), and two sites within each location (less than 500 m). We used high-performance liquid chromatography to quantify multiple BAs and a spectrophotometer to quantify chlorophyll a (Chl a). Our results show a striking degree of variation in both natural products and Chl a content. Significant variation in Chl a content occurred at the largest and smallest geographic scales. The variation patterns of BAs also occurred at the largest and smallest scales, but varied depending on which BA was analyzed. Concentrations of Chl a and isofistularin-3 were negatively correlated, suggesting that symbionts may impact the concentration of some of these compounds. Our results underline the complex control of the production of secondary metabolites, with factors acting at both small and large geographic scales affecting the production of multiple secondary metabolites.
authors.affiliation: Center for Advanced Studies of Blanes (CEAB-CSIC), Accés a la Cala St. Francesc 14, Blanes 17300, Girona, Spain.
authors.forename: Oriol
authors.initials: O
authors.lastname: Sacristan-Soriano
authors.affiliation: Environmental and Biomolecular Chemistry Laboratory, University of Perpignan Via Domitia, 52 Paul Alduy Ave., Perpignan Cedex 66860, France.
authors.forename: Bernard
authors.initials: B
authors.lastname: Banaigs
authors.affiliation: Natural Products and Agrobiology Institute (IPNA-CSIC), Avda. Astrofísico Francisco Sánchez 3, La Laguna, Tenerife 38206, Spain.
authors.forename: Mikel A
authors.initials: MA
authors.lastname: Becerro
mesh_terms: D000470:Alkaloids / Q000032:analysis*; D000818:Animals; D002734:Chlorophyll / Q000032:analysis; D000077194:Chlorophyll A; D002851:Chromatography, High Pressure Liquid; D008970:Molecular Weight; D011161:Porifera / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000470:Alkaloids; D002734:Chlorophyll; D000077194:Chlorophyll A