Identification of Pectenotoxin-11 as 34S-Hydroxypectenotoxin-2, a New Pectenotoxin Analogue in the Toxic Dinoflagellate Dinophysis acuta from New Zealand

Abstract

A new pectenotoxin, which has been named pectenotoxin-11 (PTX11), was isolated from the dinoflagellate Dinophysis acuta collected from the west coast of New Zealand. The structure of PTX11 was determined as 34S-hydroxypectenotoxin-2 by tandem mass spectrometry and UV and NMR spectroscopy. PTX11 appears to be only the third pectenotoxin identified as a natural biosynthetic product from algae after pectenotoxin-2 and pectenotoxin-12. The LD50 of PTX11 determined by mouse intraperitoneal injection was 244 microg/kg. The LD(min) of PTX11 in these experiments was 250 microg/kg. No signs of toxicity were recorded in mice following an oral dose of PTX11 at 5000 microg/kg. No diarrhea was observed in any of the animals administered with the test substance by either route of administration. Unlike pectenotoxin-2 (PTX2), PTX11 was not readily hydrolyzed to its corresponding seco acid by enzymes from homogenized green-lipped mussel (Perna canaliculus) hepatopancreas.

Co-occurrence of Dinophysis tripos and pectenotoxins in Argentinean shelf waters

“…Pectenotoxin-11 has been reported from New Zealand (Suzuki et al, 2003), the Galician Rías, Spain (Pizarro et al, 2008), North Sea (Krock et al, 2008), along the Chilean coast (Blanco et al, 2007;Krock et al, 2009;Trefault et al, 2011) and from the Benguela Current, South Africa (Pitcher et al, 2011), but this is the first report for the Argentinean Sea. Although this toxin was already associated with Dinophysis acuta (MacKenzie et al, 2005;Suzuki et al, 2006) and Dinophysis acuminata (MacKenzie et al, 2005), our data do not strongly support Dinophysis tripos being a producer of PTX-11, because there was little correlation between the toxin and the species (r = 0.67). A possible explanation for this low correlation is that D. tripos might feed on the original producer of the toxin which could be D. acuminata, as it was present in some stations.…”

“…This relation between PTX-2sa and Dinophysis spp. (8.16 pg cell À1 ) was previously reported for natural plankton food suspensions rich in Dinophysis norvegica cells (Kozlowsky- Suzuki et al, 2006). However, additional field studies as well as culture establishment are required to unambiguously elucidate the toxin profile of this species and the possible production of PTX-2sa by this genus, as well as to test its bioaccumulation in the food web.…”

LC-MS/MS Analysis of Diarrhetic Shellfish Poisoning (DSP) Toxins, Okadaic Acid and Dinophysistoxin Analogues, and Other Lipophilic Toxins

“…52 Both compounds showed many common fragment ions, but a few of the ions were shifted up or down in mass by 16 amu. Figure 13 presents a proposed assignment of fragment ions deduced from examination of the structure and through comparison of the spectra of PTX1 and PTX11.…”

“…PTX2 has been reported to be present in the toxic dinoflagellates Dinophysis spp., [36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51] which is also the causative species of OA and DTXs. Recently, several novel pectenotoxins, PTX11, 45,52 PTX12, 46 PTX13, 53 and PTX14, 53 were found in Dinophysis spp. by using LC-MS.…”

Use of Biosensors as Alternatives to Current Regulatory Methods for Marine Biotoxins

“…Although these toxins were initially classified in the DSP group, their diarrheic toxicity to humans has not been proven. Actually, it has been recently demonstrated that oral administration to mice does not cause any toxic effect, in spite of the toxicity induced by intraperitoneal administration [52,53]. The mechanism of action of pectenotoxin seems related to the disruption of the actin cytoskeleton observed in vitro [54][55][56][57].…”