This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Touzet, N.
Right arrow Articles by Raine, R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Touzet, N.
Right arrow Articles by Raine, R.
Agricola
Right arrow Articles by Touzet, N.
Right arrow Articles by Raine, R.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, May 2007, p. 3333-3342, Vol. 73, No. 10
0099-2240/07/$08.00+0     doi:10.1128/AEM.02161-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Characterization of Nontoxic and Toxin-Producing Strains of Alexandrium minutum (Dinophyceae) in Irish Coastal Waters{triangledown}

Nicolas Touzet,1* Jose M. Franco,2 and Robin Raine1

The Martin Ryan Institute, National University of Ireland, Galway, Ireland,1 Instituto Español de Oceanografía, Apto. 1552, Vigo, Spain2

Received 14 September 2006/ Accepted 19 February 2007

A comparative analysis of the morphology, toxin composition, and ribosomal DNA (rDNA) sequences was performed on a suite of clonal cultures of the potentially toxic dinoflagellate Alexandrium minutum Halim. These were established from resting cysts or vegetative cells isolated from sediment and water samples taken from the south and west coasts of Ireland. Results revealed that strains were indistinguishable, both morphologically and through the sequencing of the D1-D2 domain of the large subunit and the ITS1-5.8S-ITS2 regions of the rDNA. High-performance liquid chromatography fluorescence detection analysis, however, showed that only strains derived from retentive inlets on the southern Irish coast synthesized paralytic shellfish poisoning (PSP) toxins (GTX2 and GTX3), whereas all strains of A. minutum isolated from the west coast were nontoxic. Toxin analysis of net hauls, taken when A. minutum vegetative cells were in the water column, revealed no PSP toxins in samples from Killary Harbor (western coast), whereas GTX2 and GTX3 were detected in samples from Cork Harbor (southern coast). These results confirm the identity of A. minutum as the most probable causative organism for historical occurrences of contamination of shellfish with PSP toxins in Cork Harbor. Finally, random amplification of polymorphic DNA was carried out to determine the degree of polymorphism among strains. The analysis showed that all toxic strains from Cork Harbor clustered together and that a separate cluster grouped all nontoxic strains from the western coast.


* Corresponding author. Mailing address: The Martin Ryan Institute, National University of Ireland, Galway, Ireland. Phone: 353-91-493231. Fax: 353-91-525005. E-mail: nicolas.touzet{at}nuigalway.ie

{triangledown} Published ahead of print on 2 March 2007.


Applied and Environmental Microbiology, May 2007, p. 3333-3342, Vol. 73, No. 10
0099-2240/07/$08.00+0     doi:10.1128/AEM.02161-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:

  • Christiansen, G., Molitor, C., Philmus, B., Kurmayer, R. (2008). Nontoxic Strains of Cyanobacteria Are the Result of Major Gene Deletion Events Induced by a Transposable Element. Mol Biol Evol 25: 1695-1704 [Abstract] [Full Text]