Inhibition of photosynthesis and bleaching of zooxanthellae by the coral pathogen Vibrio shiloi
Open Access
- 1 June 1999
- journal article
- research article
- Published by Wiley in Environmental Microbiology
- Vol. 1 (3), 223-229
- https://doi.org/10.1046/j.1462-2920.1999.00027.x
Abstract
Vibrio shiloi is the causative agent of bleaching (loss of endosymbiotic zooxanthellae) of the coral Oculina patagonica in the Mediterranean Sea. To obtain information on the mechanism of bleaching, we examined the effect of secreted material (AK1‐S) produced by V. shiloi on zooxanthellae isolated from corals. AK1‐S caused a rapid inhibition of photosynthesis of the algae, as measured with a Mini‐PAM fluorometer. The inhibition of photosynthesis was caused by (i) ammonia produced during the growth of V. shiloi on protein‐containing media and (ii) a non‐dialysable heat‐resistant factor. This latter material did not inhibit photosynthesis of the algae by itself but, when added to different concentrations of NH4Cl, enhanced the inhibition approximately two‐ to threefold. Ammonia and the enhancer were effective to different degrees on zooxanthellae isolated from four species of coral examined. In addition to the rapid inhibition of photosynthesis, AK1‐S caused bleaching (loss of pigmentation) and lysis of zooxanthellae. Bleaching was more rapid than lysis, reaching a peak (25% bleached algae) after 6 h. The factors in AK1‐S responsible for bleaching and lysis were different from those responsible for the inhibition of photosynthesis, because they were heat sensitive, non‐dialysable and active in the dark. Thus, the coral pathogen V. shiloi produces an array of extracellular materials that can inhibit photosynthesis, bleach and lyse zooxanthellae.Keywords
This publication has 34 references indexed in Scilit:
- Fluctuations in algal chlorophyll and carotenoid pigments during solar bleaching in the coral Goniastrea aspera at Phuket, ThailandMarine Ecology Progress Series, 1997
- Algicidal Marine Bacteria Isolated from Northern Hiroshima Bay, JapanFisheries Science, 1995
- Periodic mass-bleaching and elevated sea temperatures:bleaching of outer reef slope communities in Moorea, French PolynesiaMarine Ecology Progress Series, 1995
- Temperature Stress Causes Host Cell Detachment in Symbiotic Cnidarians: Implications for Coral BleachingThe Biological Bulletin, 1992
- Elimination of Two Reef-Building Hydrocorals Following the 1982-83 El Niño Warming EventScience, 1991
- Coral reef bleaching in the 1980s and possible connections with global warmingTrends in Ecology & Evolution, 1991
- Response of Hawaiian and other Indo-Pacific reef corals to elevated temperatureCoral Reefs, 1990
- The relationship between the quantum yield of photosynthetic electron transport and quenching of chlorophyll fluorescenceBiochimica et Biophysica Acta (BBA) - General Subjects, 1989
- Interactions Between Bacteria and Algae in Aquatic EcosystemsAnnual Review of Ecology and Systematics, 1982
- Inhibition of Photosystem II by uncouplers at alkaline pH and its reversal by artificial electron donorsBiochimica et Biophysica Acta (BBA) - Bioenergetics, 1975