CORAL BIOMINERALIZATION: AN INTERDISCIPLINARY APPROACH FOR PRESERVATION OF ENDANGERED FAUNA

Scleractinian corals are abundant on the Brazilian coast and are fundamental in the formation of reefs, regions of great biodiversity and social and economic importance for coastal communities. Due to human action, seawater is becoming more acidic and turbid, harming fauna and flora. In this context, the present work aims to study the biomineralization process, that is, the biological process of formation of calcium carbonate skeletons by corals of the order Scleractinia to promote their preservation. We combine Molecular Biology and Materials Sciences, as well as computational methods, to study the fundamentals of coralline biomineralization: the material and the formation mechanisms. Four proteins found in the model organism S. pistillata (Esper, 1972), known as CARPs (Coral Acid Rich Proteins), will be studied for their three-dimensional structure through crystallography, activity and stability by thermo-fluorescence, dynamic light scattering, and circular dichroism. Additionally, this work aims to start identifying biomineralizing proteins for brazilian species for future comparison of calcifying machinery. Three protein extraction methods are being tested for different protein outputs: TRIzol, BEPER and phenol-based extraction. Coral skeletons will have their crystal structure and elemental composition studied by XRPD and EDS, as well as their thermal stability through TG (25^oC to 800^oC). Until now, CARP1 and CARP4 have been purified and are under investigation for their stability from pH 6.0 to 8.0 and temperatures 25^oC to 100^oC through thermo-fluorescence. Coral skeleton samples revealed acicular aragonite crystalline structure and aragonite-calcite phase transition between 285^oC and 400^oC. The project values ​​the national fauna, promotes research and preservation. It is internationally relevant, as it complies with the 14th of the UN 17 Sustainable Development Goals, Life in Water.