000211075 001__ 211075
000211075 005__ 20190317000246.0
000211075 0247_ $$2doi$$a10.1016/j.cbpa.2015.08.012
000211075 022__ $$a1095-6433
000211075 02470 $$2ISI$$a000363825300003
000211075 037__ $$aARTICLE
000211075 245__ $$aDifferential coral bleaching—Contrasting the activity and response of enzymatic antioxidants in symbiotic partners under thermal stress
000211075 260__ $$bElsevier$$c2015$$aNew York
000211075 269__ $$a2015
000211075 300__ $$a11
000211075 336__ $$aJournal Articles
000211075 520__ $$aMass coral bleaching due to thermal stress represents a major threat to the integrity and functioning of coral reefs. Thermal thresholds vary, however, between corals, partly as a result of the specific type of endosymbiotic dinoflagellate (Symbiodinium sp.) they harbour. The production of reactive oxygen species (ROS) in corals under thermal and light stress has been recognised as one mechanism that can lead to cellular damage and the loss of their symbiont population (Oxidative Theory of Coral Bleaching). Here, we compared the response of symbiont and host enzymatic antioxidants in the coral species Acropora millepora and Montipora digitata at 28 °C and 33 °C. A. millepora at 33 °C showed a decrease in photochemical efficiency of photosystem II (PSII) and increase in maximum midday excitation pressure on PSII, with subsequent bleaching (declining photosynthetic pigment and symbiont density). M. digitata exhibited no bleaching response and photochemical changes in its symbionts were minor. The symbiont antioxidant enzymes superoxide dismutase, ascorbate peroxidase, and catalase peroxidase showed no significant upregulation to elevated temperatures in either coral, while only catalase was significantly elevated in both coral hosts at 33 °C. Increased host catalase activity in the susceptible coral after 5 days at 33 °C was independent of antioxidant responses in the symbiont and preceded significant declines in PSII photochemical efficiencies. This finding suggests a potential decoupling of host redox mechanisms from symbiont photophysiology and raises questions about the importance of symbiont-derived ROS in initiating coral bleaching.
000211075 6531_ $$aAPX
000211075 6531_ $$aAcropora millepora
000211075 6531_ $$aCAT
000211075 6531_ $$aGlobal change
000211075 6531_ $$aMontipora digitata
000211075 6531_ $$aOxidative Stress
000211075 6531_ $$aSOD
000211075 6531_ $$aSymbiodinium
000211075 6531_ $$aSymbiosis
000211075 6531_ $$aThermal biology
000211075 700__ $$0247958$$g244120$$aKrüger, Thomas
000211075 700__ $$aHawkins, Thomas
000211075 700__ $$aBecker, Susanne
000211075 700__ $$aPontasch, Stefanie
000211075 700__ $$aDove, Sophie
000211075 700__ $$aHoegh-Guldberg, Ove
000211075 700__ $$aLeggat, William
000211075 700__ $$aDavy, Simon
000211075 773__ $$j190$$tComparative Biochemistry and Physiology Part a Molecular and Integrative Physiology$$q15-25
000211075 8564_ $$uhttps://infoscience.epfl.ch/record/211075/files/1-s2.0-S1095643315002251-main.pdf$$zn/a$$s1643022$$yn/a
000211075 909C0 $$xU12552$$0252426$$pLGB
000211075 909CO $$ooai:infoscience.tind.io:211075$$qGLOBAL_SET$$particle$$pENAC
000211075 917Z8 $$x244120
000211075 937__ $$aEPFL-ARTICLE-211075
000211075 973__ $$rREVIEWED$$sPUBLISHED$$aEPFL
000211075 980__ $$aARTICLE