Viruses as a Regulator of Harmful Algal Bloom Activity: Aureococcus anophagefferens as a Model System

EPA Grant Number: R829367
Title: Viruses as a Regulator of Harmful Algal Bloom Activity: Aureococcus anophagefferens as a Model System
Investigators: Gastrich, Mary Downes , Anderson, O. Roger , Gobler, Christopher , Wilhelm, Steven W.
Institution: Columbia University in the City of New York , Long Island University - Southampton College , University of Tennessee - Knoxville
Current Institution: Columbia University in the City of New York , Long Island University - Southampton College , University of Tennessee - Knoxville
EPA Project Officer: Hiscock, Michael
Project Period: January 15, 2002 through July 31, 2005 (Extended to January 14, 2006)
Project Amount: $210,232
RFA: Ecology and Oceanography of Harmful Algal Blooms (2001) RFA Text |  Recipients Lists
Research Category: Aquatic Ecosystems , Water Quality , Water , Ecosystems

Description:

The potential for viral activity to serve as a control on population densities of the bloom forming alga, Aureococcus anophagefferens, will be evaluated to contribute to our knowledge of the complexity and dynamic interplay of the virus-host interaction, and to an understanding of why these algae continue to bloom in certain areas at certain times and then quickly disappear. The hypothesis being tested is that viral infection will account for greater mortality in blooms in natural populations of A. anophagefferens than other environmental or biological factors (e.g., grazing, water quality parameters, etc.). The objectives of this study are to: 1) determine the frequency that viral-like particles (VLPs) infect and lyse natural populations of A. anophagefferens in coastal bays of New York and New Jersey; 2) isolate viruses specific to A. anophagefferens and establish baseline information on the genetic diversity of viruses that infect A. anophagefferens; and 3) determine the influence of viral activity on the proliferation of A. anophagefferens and bloom termination in situ.

Approach:

The approach includes laboratory methods which will clarify the role of viral infection in controlling brown tide blooms collection of field samples to monitor density of VLP-infected A. anophagefferens, screening of field-collected water to isolate naturally occurring viruses, transmission electron microscopy validation of the laboratory and field work, purification of viral isolates specific to A. anophagefferens, isolation of viral DNA to determine genetic diversity of viruses infecting A. anophagefferens, Proctor method to estimate viral-induced mortality rates and duration of lytic cycle, one-step growth experiments to assess length of the lytic cycle and experiments with field-collected natural populations of A. anophagefferens to assess effects of viral infection.

Expected Results:

The significance of this study is that it will determine whether viral infection will account for greater mortality in blooms in natural populations of A. anophagefferens than other environmental factors (e.g., grazing, water quality parameters, etc.) and to provide a comprehensive documentation of the viral-host interaction that can be used by scientists and environmental managers (e.g., develop future risk assessments and strategies for management of brown tide blooms in the NY-NJ northeast region). This will improve our understanding of the role of viral infection in the control and cessation of brown tide blooms, and the extent to which residual algal populations, resistant to the virus, may be contributing to subsequent growth and re-establishment of blooms.

Publications and Presentations:

Publications have been submitted on this project: View all 6 publications for this project

Journal Articles:

Journal Articles have been submitted on this project: View all 2 journal articles for this project

Supplemental Keywords:

viruses, harmful algal blooms, Aureococcus anophagefferens., RFA, Scientific Discipline, Water, Ecosystem Protection/Environmental Exposure & Risk, Ecology, Aquatic Ecosystems & Estuarine Research, Ecosystem/Assessment/Indicators, Ecosystem Protection, Chemistry, Environmental Microbiology, Aquatic Ecosystem, Ecological Effects - Environmental Exposure & Risk, algal blooms, Biology, mortality rate, harmful algal blooms, control of algal blooms, Auerococcus, brown tide blooms, ECOHAB, water quality

Progress and Final Reports:

  • 2002 Progress Report
  • 2003 Progress Report
  • 2004
  • Final Report