Researchers at Scripps Institution of Oceanography at UC San Diego have identified a potential red tide killer. Red tides and related phenomena in which microscopic algae accumulate rapidly in dense concentrations have been on the rise in recent years, causing hundreds of millions of dollars in worldwide losses to fisheries and beach tourism activities. Despite their wide-ranging impacts, such phenomena, more broadly referred to as harmful algal blooms, remain unpredictable in not only where they appear, but how long they persist.
New research at Scripps has identified a little-understood but common marine microbe as a red tide killer, and implicates the microbe in the termination of a red tide in Southern California waters in the summer of 2005.
While not all algal outbreaks are harmful, some blooms carry toxins that have been known to threaten marine ecosystems and even kill marine mammals, fish and birds.
Using a series of new approaches, Scripps Oceanographys Xavier Mayali investigated the inner workings of a bloom of dinoflagellates, single-celled plankton, known by the species name Lingulodinium polyedrum. The techniques revealed that so-called Roseobacter-Clade Affiliated (RCA cluster) bacteriaseveral at a timeattacked individual dinoflagellate by attaching directly to the planktons cells, slowing their swimming speed and eventually killing them.
Using DNA evidence, Mayali matched the identity of the RCA bacterium in records of algal blooms around the world.
In fact, it turns out that RCA bacteria are present in temperate and polar waters worldwide. Mayalis novel way of cultivating these organisms has now opened up a new world of inquiry to understand the ecological roles of these organisms. The first outcome of this achievement is the recognition of the bacteriums potential in killing red-tide organisms.
Its possible that bacteria of this type play an important role in terminating algal bloom
|Contact: Mario Aguilera or Annie Reisewitz|
University of California - San Diego