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6 Pseudo-nitzschia dolorosa: (A) SEM. Acid cleaned frustules showing the valve of the cell at valve view. Valve margins are asymmetry, straight at one side and convex on the other side. Scale bar = 10 µm. (B) Central part of the cell showing the present of large central interspace, eccentric raphe divided by a central nodule. Scale bar = 1 µm. (C) End of the valve, rapidly tapering apices. Scale bar = 1 µm. (D) TEM. Parts of the valve, showing one row of square poroids. Scale bar = 1 µm.
Source publication
The genus Pseudo-nitzschia is one of the most well studied marine diatoms as fifteen of the species are known to produce the neurotoxin, domoic acid (DA) that is responsible for Amnesic Shellfish Poisoning (ASP). Thus far, little attention is given to the distribution of Pseudo-nitzschia spp. in Malaysia. In this study, three species of Pseudo-nitz...
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Species of the diatom Pseudo-nitzschia are known to produce domoic acid that is responsible for amnesic
shellfish poisoning (ASP). To investigate the potential risk of ASP and species occurrence of toxic or potentially toxic Pseudo-nitzschia in Malaysian waters, plankton samples were collected from 17 locations. Samples were examined through transm...
Some diatoms of the genera Pseudo-nitzschia and Nitzschia produce the neurotoxin domoic acid (DA), a compound that caused amnesic shellfish poisoning (ASP) in humans just over 30 years ago (December 1987) in eastern Canada. This review covers new information since two previous reviews in 2012. Nitzschia bizertensis was subsequently discovered to be...
The diatom Pseudo-nitzschia has been known for domoic acid poisoning, or better known as Amnesic Shellfish Poisoning (ASP). Accumulation of domoic acid (DA) in commercial bivalves during the bloom of this toxic diatom has caused economic losses to the industry. To clarify the status of ASP and the diversity of toxic or potentially toxic Pseudo-nitz...
Domoic acid (DA) is a hapten, kainic acid and a potent neurotoxin. Upon exposure, it causes amnesic shellfish
poisoning (ASP). The toxin is produced by microscopic algae, specifically diatomic genus known as Pseudo-nitzschia. DA
is accumulated in shellfish, sardines, and anchovies. Poisoning results in human and other marine mammals, when they eat...
Citations
... The Pseudonitzschia had been well documented in Vietnam with thirteen species found but not in other countries in Southeast Asia region (Larsen and Nguyen, 2004). In order to gain better understanding on occurrence, taxonomy, seasonal distribution and physiology of dolorosa, P. micropora and P. pungens had been confirmed in Malaysian waters (Lim, 2011;Su, 2011). Although P. brasiliana and P. pungens was reported elsewhere as potential toxin producer of domoic acid (Whyte et al., 1995;Sahraoui et al., 2011;Moschandreou et al., 2012), but none of the strains found in Malaysia showed detectable level of domoic acid . ...
... Very few studies have reported on the occurrence and distribution of Pseudonitzschia species in Malaysian waters (Lim, 2011;Su, 2011). The aim of this study is to document the occurrence and distribution of Pseudo-nitzschia in Malaysian waters. ...
... pungens are reported as widely distributed in Malaysian coastal waters Su, 2011;Lim, 2011;Lim et al., 2012b;2012c). This present study records for the first time the occurrence of P. cf. cuspidata, P. dolorosa, and P. circumpora in Malaysian waters. ...
... In Malaysian coastal waters, studies of Pseudo-nitzschia were initiated in 2007, in Kuching estuaries, the southeastern part of Borneo (Lim 2011, Su 2011, Lim et al. 2012b. Cell abundance of Pseudo-nitzschia in the study area, even though relatively low (data not shown), showed a high species diversity, with five species documented, including a new species, P. circumpora (Lim et al. 2012a). ...
A study on the morphology and phylogeny of 18 strains of Pseudo-nitzschia established from the Strait of Malacca, Peninsular Malaysia, was undertaken. Morphological data combined with molecular evidence show that they constitute three new species, for which the names, P. batesiana sp. nov., P. lundholmiae sp. nov., and P. fukuyoi sp. nov., are proposed. The three new species closely resemble species in the P. pseudodelicatissima complex sensu lato. Morphologically, P. batesiana differs from other species in the complex by having a smaller part of cell overlapping in the chain, whereas P. lundholmiae differs by having fewer poroid sectors and P. fukuyoi by having a distinct type of poroid sectors. Nucleotide sequences of the LSU rDNA (D1-D3) of the three new species reveal significant nucleotide sequence divergence (0.1 to 9.3%) from each other and from other species in the P. pseudodelicatissima complex s.l. The three species are phylogenetically closely related to species in the P. pseudodelicatissima complex, with P. batesiana appearing as a sister taxon to P. circumpora, P. caciantha and P. subpacifica; while P. lundholmiae and P. fukuyoi are more closely related to P. pseudodelicatissima and P. cuspidata. The three species show 2-3 compensatory base changes (CBCs) in their ITS2 transcripts when compared to the closely related species. The ITS2 with its structural information has proven its robustness in constructing a better resolved phylogenetic framework for Pseudo-nitzschia.
