CS16 Harmful Algal Blooms
Date: Wednesday, June 12, 2002
Location: Poster Session - VCC
 
HenryMS, Mote Marine Laboratory, Sarasota, FL, USA, mhenry@mote.org
Kirkpatrick, G, J, Mote Marine Laboratory, Sarasota, FL, USA, gkirkpat@mote.org
Pierce, R, H, Mote Marine Laboratory, Sarasota, FL, USA, rich@mote.org
Blum, P, C, Mote Marine Laboratory, Sarasota, FL, USA, pcblum@mote.org
Chrismer, L, K, Mote Marine Laboratory, Sarasota, FL, USA, lkchris@mote.org
 
INTRA- AND EXTRA-CELLULAR BREVETOXIN CONCENTRATIONS DURING A KARENIA BREVIS DIEL CYCLE
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Karenia brevis, the organism responsible for the Florida red tide, produces several potent neurotoxins that can cause massive fish kills, shellfish contamination and respiratory irritation. Questions remain regarding the amount of the various brevetoxins produced as well as the toxins disposition during a diel cycle. Three diel cycles of a natural K. brevis bloom near Sarasota, FL (September 2001) were studied to determine the amount of brevetoxin within the cell (intra-cellular) and in the surrounding water (extra-cellular). Cells were separated from the surrounding water using a cell (Amicon) concentrator fitted with a 5 um polycarbonate filter. Toxins were extracted using C-18 extraction discs. Cell enumeration and size were determined using a Coulter Multisizer® to predict the time of cell division. Microscopic cell counts were also conducted. Toxin concentrations and their relationship to the diel cycle are presented. Preliminary data indicate that toxin production per cell was maximized between 11:00 AM and 2:00 PM local time. Total toxin concentrations were divided between the intra-cellular and extra-cellular components throughout the cycle, with Pbtx-3 occurring primarily outside the cell.