NURP banner graphic
Home About Research Technology Centers News Funding Library
Press Releases

Bacteria Give Coral an Orange Glow
This story entered on 4th Oct, 2004 05:53:04 AM PST

NURP-sponsored research published in Science article has contributed to the discovery that cyanobacteria are responsible for the orange glow emitted from Montastraea cavernosa. The great star coral M. cavernosa occurs in a diverse array of colors because it possesses genes that code for cyan, red, and green fluorescent proteins. However, M. cavernosa can also emit an orange glow, which does not originate from the coral. The orange glow is emitted from symbiotic cyanobacteria, a photosynthetic bacterium.

The study results suggest that cyanobacteria, which reside in M. cavernosa's epithelial cells, absorbs light energy and transforms it to a red-orange hue that fluoresces as an orange glow due to the weak energy coupling of red and orange pigments within cyanobacteria. The research, led by Michael Lesser from the University of New Hampshire and supported by NURP's Caribbean Marine Research Center, also suggests that cyanobacteria has a symbiotic relationship with its coral host; the cyanobacteria provides an important service for it's host by releasing nitrogenase, an enzyme which converts the nitrogen found in seawater to a form usable by the coral.

Cyanobacteria may also provide a usable form of nitrogen to zooxanthellae, which provides M. cavernosa with its carbon requirements. In addition, zooxanthellae may also supply carbon to cyanobacteria, suggesting a symbiotic relationship between the two organisms. The presence of cyanobacteria in corals highlights the important role that symbiotic relationships can potentially play in species diverse coral reefs and adds another level of complexity to the ecology and biology of corals.

The study is published in Science (see citation below) and was featured on MSNBC and the BBC.

Michael P. Lesser, Charles H Mazel, Maxim Y. Gorbunov, Paul G. Falkowski (2004). Discovery of Symbiotic Nitrogen-Fixing Cyanobacteria in Corals. Science. Vol. 305, Aug 13, 2004, pp. 997 - 1000.

More information: Click here

Contact information
Name: John Marr
Tel: (561) 741-192


NURP logo Home   About   Research   Technology   Centers   News   Funding   Library
NOAA's Undersea Research Program
1315 East-West Highway, R/NURP - Silver Spring, MD 20910
Phone: (301) 734-1000  Fax: (301) 713-1967  
bullet  Contact Info bullet  Privacy Policy bullet  Disclaimer bullet Site Index
NOAA logo
Updated: April 1, 2005