Phycoerythrin Signatures in the Littoral Zone

Abstract

Abstract : Phycoerythrin (PE) refers to a family of highly fluorescent photosynthetic pigments found in some marine phytoplankton. In subtropical and temperate waters, PE-producing organisms are common enough that a spectral signature for PE can be obtained from bulk seawater, regardless of the concentration or type of other colored materials in the water. This project had two goals: to determine if the PE spectral signature of a water mass carries oceanographically useful information and to determine the biological mechanism by which the PE spectral signature changes in a water mass. The project showed that the nutrient status and color of oceanic waters can be inferred from PE spectral signature and that there is a distinctive PE spectral signature associated with turbid coastal water. We discovered several new types of PE-containing marine picocyanobacteria, described a totally new biochemical mechanism by which PE-containing phytoplankton can adapt to changes in the spectral quality of available light, and showed that lateral gene transfer is a key mechanism of evolution for PE and other genes in picocyanobacteria.