title: Azadinium poporum from the Argentine Continental Shelf, Southwestern Atlantic, produces azaspiracid-2 and azaspiracid-2 phosphate.
abstract: The marine dinophycean genus Azadinium has been identified as the primary source of azaspiracids (AZA), a group of lipophilic phycotoxins known to accumulate in shellfish. Blooms of Azadinium in the southern Atlantic off Argentina have been described from the 1990s, but due to a lack of cultures, the diversity of South-Atlantic Azadinium has not yet been fully explored and their toxin production potential is completely unknown. During a spring 2010 research cruise covering the El Rincón (ER) estuarine system (North Patagonian coast, Argentina, Southwestern Atlantic) a search was conducted for the presence of Azadinium. Although neither Azadinium cells nor AZA in field plankton samples were detected, 10 clonal strains of Azadinium poporum were successfuly established by incubation of sediment samples. Argentinean A. poporum were more variable in size and shape than the type description but conformed to it by the presence of multiple pyrenoids with starch sheath, in plate pattern and arrangement, and in the position of the ventral pore located on the left side of the pore plate. In contrast to all previous description of A. poporum, isolates of the Argentinean A. poporum possessed a distinct field of pores on the second antapical plate. Conspecificity of the Argentinean isolates with A. poporum was confirmed by molecular phylogeny of concatenated ITS and LSU rDNA sequences, where all Argentinean isolates together with some Chinese A. poporum strains formed a well-supported ribotype clade within A. poporum. All isolates produced AZA with the same profile, consisting of AZA-2 as the major compound and, to a lesser extent, its phosphated form. This is the first report of a phosphated marine algal toxin. This first confirmation of the presence of AZA producing Azadinium in the Argentinean coastal area underlines the risk of AZA shellfish contamination episodes in the Southwestern Atlantic region.
authors.affiliation: Alfred Wegener Institute, Am Handelshafen 12, D-27570 Bremerhaven, Germany. Electronic address: urban.tillmann@awi.de.
authors.forename: Urban
authors.initials: U
authors.lastname: Tillmann
authors.affiliation: Instituto Geológico del Sur (CONICET - Universidad Nacional del Sur), Departamento de Geología, Laboratorio de Palinología, San Juan 670, 8000 Bahía Blanca, Argentina.
authors.forename: C Marcela
authors.initials: CM
authors.lastname: Borel
authors.affiliation: Instituto Argentino de Oceanografía, Biogeoquímica Marina, IADO - CONICET, Camino la Carrindanga km 7,5 c.c. 804, B8000FWB, Bahía Blanca, Argentina.
authors.forename: Facundo
authors.initials: F
authors.lastname: Barrera
authors.affiliation: Instituto Argentino de Oceanografía, Biogeoquímica Marina, IADO - CONICET, Camino la Carrindanga km 7,5 c.c. 804, B8000FWB, Bahía Blanca, Argentina.
authors.forename: Rubén
authors.initials: R
authors.lastname: Lara
authors.affiliation: Alfred Wegener Institute, Am Handelshafen 12, D-27570 Bremerhaven, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Krock
authors.affiliation: División Ficología, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Paseo del Bosque s/n, B1900FWA, La Plata, Argentina.
authors.forename: Gastón O
authors.initials: GO
authors.lastname: Almandoz
authors.affiliation: Bruker Daltonik GmbH, Fahrenheitstr. 4, 28359 Bremen, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Witt
authors.affiliation: Centro de Genómica y Bioinformática, Universidad Mayor, Camino La Pirámide 5750, Huechuraba, Santiago, Chile.
authors.forename: Nicole
authors.initials: N
authors.lastname: Trefault
keywords: Argentina; Azadinium; Azaspiracids; Southwestern Atlantic