2001 Progress Report: Culturing and Cryopreserving Pfiesteria-like OrganismsEPA Grant Number: R826793
Title: Culturing and Cryopreserving Pfiesteria-like Organisms
Investigators: Andersen, Robert A.
Institution: Bigelow Laboratory for Ocean Sciences
EPA Project Officer: Hiscock, Michael
Project Period: October 1, 1998 through September 30, 2001 (Extended to September 30, 2002)
Project Period Covered by this Report: October 1, 2000 through September 30, 2001
Project Amount: $275,002
RFA: Ecology and Oceanography of Harmful Algal Blooms (1998) RFA Text | Recipients Lists
Research Category: Water Quality , Harmful Algal Blooms , Water , Ecosystems
Objective:Pfiesteria piscicida and related organisms (Pfiesteria-like organisms) have been suggested to be involved in fish kills and human health problems. One objective of this study is to establish cultures of these organisms so that other research scientists are able to conduct experimental studies. Samples are collected from areas where Pfiesteria-like organisms occur or are suspected to occur, and single cells are isolated using the micropipette method. The isolates are deposited in the Provasoli-Guillard National Center for Culture of Marine Phytoplankton. The second objective of the study is to develop methods for cryopreserving the cultures. Microorganisms sometimes change in culture after prolonged periods of perpetually transferring from old culture to new medium. Furthermore, perpetual transfer requires handling every few weeks, and human error can occur during this handling (e.g., mislabeled tubes, contamination, breakage or spillage). Finally, workers might be exposed to toxins when making perpetual transfers, and the level of toxins produced by cells may change during prolonged periods of perpetual transfer. Cryopreservation involves freezing the cells in such a manner that when they are thawed, they will still be alive and growing. Cryopreserved cells are maintained at a temperature of at least -1551C, or colder, by placing the frozen cells in storage tanks cooled with liquid nitrogen. Once frozen, the cells undergo no change, there is no handling, toxicity remains unchanged, and toxin exposure is eliminated.
During the past year, 10 strains of Pfiesteria were isolated and deposited. The CCMP also has deposited a Pfiesteria piscicida strain from Pat Tester (NOAA) and a Pfiesteria shumwayae from the VIMS group during the past year. This brings the total of Pfiesteria and Pfiesteria-like strains held in the CCMP to 51, of which 46 have been isolated as part of this grant.
We have successfully Cryopreserved 31 of the 51 strains, and we are currently trying to freeze the remaining strains (primary reason for the no-cost extension). The method we developed is not complicated, but it is labor intensive, and it takes considerable time to grow, filter, and freeze the cells.
Future Activities:During the next year, we plan to finish the cryopreservation of strains, complete the manuscript describing the cryopreservation techniques, and write the final grant report.
Journal Articles on this Report : 1 Displayed | Download in RIS Format
|Other project views:||All 2 publications||1 publications in selected types||All 1 journal articles|
||Sullivan BE, Andersen RA. Salinity tolerances of 62 strains of Pfiesteria and Pfiesteria-like heterotrophic flagellates (Dinophyceae). Phycological Research 2001;49(3):207-214.||