Wildfire-derived methoxyphenol pollutants impair coral calcification

Area of Science:

• Marine Biology
• Environmental Toxicology
• Biochemistry

Background:

• Wildfire pollutants are emerging stressors on marine ecosystems.
• The impact of wildfire pollutants on coral calcification is poorly understood.
• Coral reefs are vital habitats threatened by climate change and pollution.

Purpose of the Study:

• To elucidate the mechanisms by which wildfire-derived methoxyphenols (MPs) impair calcification in Acropora muricata.
• To identify the molecular and physiological pathways affected by MPs exposure.
• To establish a mechanistic link between wildfires and coral reef degradation.

Main Methods:

• Integrated approach combining physiological assays, molecular dynamics simulations, and multi-omics analysis.
• Exposure of Acropora muricata to 2,6-dimethoxyphenol (DMP).
• Analysis of oxidative stress markers, gene expression, enzyme activity, and skeletal density.

Main Results:

• DMP exposure induces oxidative stress (glutathione depletion, ROS bursts) and DNA damage.
• DMP disrupts energy homeostasis, inhibits carbonic anhydrase (CA) activity, and alters coral-associated bacterial communities.
• Calcification collapsed, reducing skeletal density by ~30%, due to a cascade initiated by oxidative stress, amplified by energy imbalance, and driven by CA inhibition.

Conclusions:

• Wildfire-derived MPs are a previously unrecognized driver of coral calcification failure.
• A mechanistic link is established between terrestrial wildfires and accelerated reef degradation.
• These impacts are likely exacerbated by climate change, posing a significant threat to coral reef ecosystems.