Protoperidinium crassipes

Figure 17.1. Protoperidinium crassipes. Average dimensions 0.1 x 0.12 mm. Reprinted from James et al. 2003, with permission from Elsevier.

Azaspiracids [azaspiracid-1 (18)] are another class of highly unusual polyketide polyethers originally isolated from Irish mussels that caused azaspiracid shellfish poisoning (5). They are produced by the dinoflagellate Protoperidinium crassipes. A similar class of polyether toxins named pinnatoxins [pinnatoxin A (19)] were reported from the bivalve Pinna pectinata a closely related species P. attenuata is known to cause food poisoning in China. Pinnatoxins are likely of dinoflagellate origin and activate Ca channels (15). 

Azaspiracids Not fully established. Possibly Protoperidinium crassipes... 

Like other Protoperidinium species, P. crassipes is a pallium-feeder, that is, extends a spider web-like structure or pseudopodium called a pallium to trap prey (other diatoms and dinoflagellates) digestion is extracellular [81], Successful cultures of P crassipes on L. polyedra have been described [82]. 

Several Dinophysis species are the main worldwide sources of OAs and PTXs. YTXs prodnced by L. polyedra, P. reticulatum, and G. spinifera are a more recently identified problem. Widespread application of LC-MS analyses will lead to identification of a mnch larger hst of cansative species. AZP toxins, so far associated with P. crassipes, seem to be a Enropean problem, bnt their presence has not been properly explored elsewhere. Bloom dynamics, toxin profiles, and toxin content per cell need to be stndied on regional and local scales. Some key issnes that reqnire farther research and/or improved procedures and tools are (a) genetic (inter- and intraspecific) variabihty of Dinophysis spp. (b) identification of inocnlnm popnlations and other behavioral processes (c) toxin production studies in cnltnres of Dinophysis and Protoperidinium spp. and (d) improved determination of hidden toxins, snch as diol esters of OA, in microalgal extracts. 

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