Published in Abstracts of 2007 American Society of Limnology and Oceanography
Annual Meeting
Olson, N.D., University of Hawai`i at Hilo, Hawai`i, USA nolson@hawaii.edu
Takabayashi, M., University of Hawai`i at Hilo, Hawai`i, USA misakita@hawaii.edu
THE NITROGENASE EXPRESSION OF A DIAZOTROPHIC CYANOBACTERIAL
SYMBIONT IN CORALS AND ITS POTENTIAL ROLE IN THE CORAL REEF
NITROGEN CYCLE.
Coral and its dinoflagellate symbiont have been classically viewed as survivors of a
nitrogen poor environment. The recent discovery of a nitrogen-fixing cyanobacterial
symbiont within a Caribbean coral complicates this model. The discovery of these
cyanobacteria and a suite of other bacterial symbionts, calls for the current understanding
of the nitrogen interdependency within coral holobiont to be reevaluated. We are
searching for similar cyanobacterial symbiots in Hawaiian corals, using PCR of the
nitrogenase gene (nifH), which encodes for the enzyme responsible for fixation of
atmospheric nitrogen. nifH-specific PCR has yielded products from a few species of
Hawaiian corals that were thoroughly rinsed with filtered seawater to remove
contaminants. Verification of these sequences will be followed by taxonomic analysis of
these cyanobacteria. Further, the diel variability in the expression of nitrogenase by these
cyanobacterial symbionts will be analyzed by quantitative PCR (qPCR) of nifH. The
implications for this study have the potential to dramatically affect the current view of the
coral reef nitrogen cycle.
SS23: CONUNDRUM AND CONTROVERSIES: WHAT CONTRIBUTES TO THE
VERTICAL FLUX OF CARBON, NITROGEN, AND PHOSPHORUS IS AQUATIC
ECOSYSTEMS?
CS10: EUTROPHICATION AND NUTRIENT CYCLING
SS12: ASLO MULTICULTURAL STUDENT SYMPOSIUM
Oral
Olson, N.D.