Pfiesteria

Pfiesteria is a genus of dinoflagellates, named for the late Dr. Lois Pfiester, a biologist who did much of the early research on the genus.

Pfiesteria (Pfiesteria piscicida) is a dinoflagellate which some researchers claimed was toxic and in large blooms was responsible for fish kills in the 1980s and 1990s on the coast of North Carolina and in tributaries of the Chesapeake Bay. While some experts say the dinoflagellate is not toxic, peer-reviewed evidence exists showing that it is.

While some peer-reviewed research by government and university dinoflagellate experts has suggested that its living cycle is extremely complex (these scientists have found at least 24 different stages, spanning from cyst to several amoeba-like forms), other peer-reviewed research by government and university dinoflagellate experts has found only a simple life cycle with no toxic amoebic stage. The original research claimed that the organism apparently moves through many different stages as environmental conditions require. However, research from 2002 claims the cycle is much simpler than previously thought (See external Links), and that the true Pfiesteria is non-toxic. Some peer-reviewed research based on advanced DNA analyses shows that the organism lacks certain genetic structure to be capable of making the type of toxic proteins associated with typical dinoflagellates. However, researchers from the NOAA National Centers for Coastal Ocean Science, the National Institute of Standards and Technology, the Medical University of South Carolina, and the College of Charleston (S.C.) have formally isolated and characterized the toxin in the estuarine dinoflagellete Pfiesteria piscicida and also have identified how the organism transforms from a non-toxic to toxic state. The findings were published in the peer-reviewed science journal, Environmental Science and Technology, on January 11, 2007.