Title

Localization of Polyketide Synthase Encoding Genes to the Toxic Dinoflagellate Karenia brevis

Document Type

Article

Publication Date

8-2005

Keywords

Karenia brevis, Brevetoxin, Polyketide synthase, Dinoflagellate, Fluorescence in situ hybridization

Publication Title

Phytochemistry

ISSN

0031-9422

Volume

66

Issue/No.

15

First Page

1767

Last Page

1780

Peer Reviewed

1

Abstract

Karenia brevis is a toxic marine dinoflagellate endemic to the Gulf of Mexico. Blooms of this harmful alga cause fish kills, marine mammal mortalities and neurotoxic shellfish poisonings. These harmful effects are attributed to a suite of polyketide secondary metabolites known as the brevetoxins. The carbon framework of all polyketides is assembled by a polyketide synthase (PKS). Previously, PKS encoding genes were amplified from K. brevis culture and their similarity to a PKS gene from the closely related protist,Cryptosporidium parvum, suggested that these genes originate from the dinoflagellate. However, K. brevishas not been grown axenically. The associated bacteria might be the source of the toxins or the PKS genes. Herein we report the localization of PKS encoding genes by a combination of flow cytometry/PCR and fluorescence in situ hybridization (FISH). Two genes localized exclusively to K. brevis cells while a third localized to both K. brevis and associated bacteria. While these genes have not yet been linked to toxin production, the work describes the first definitive evidence of resident PKS genes in any dinoflagellate.

Comments

©2005 Elsevier Ltd. All rights reserved.

Additional Comments

NIH/NIEHS grant #s: S11 ES111181, P30 ES 05705; NIH/NIGMS grant #s: S06 GM008205, R25 GM061347; NSF grant #: 9974984

ORCID ID

0000-0002-1637-4125

ResearcherID

F-8809-2011

DOI

10.1016/j.phytochem.2005.06.010