Structure And Thermal Stability Of A Coral Metabolic Enzyme

Increased ocean temperatures can lead to coral bleaching, as the symbiotic relationship between coral and photosynthetic algae breaks down. The molecular details of this temperature‐dependent disruption are not well understood. Here, we investigate the thermal stability of a critical metabolic enzyme, glyceraldehyde‐3‐phosphate dehydrogenase, from the stony coral Acropora millepora. Binding of the cofactor NAD increases the melting temperature of the enzyme by fully 10 °C. In order to identify the basis for this stabilization, we then determined the crystal structure of the cofactor‐enzyme complex (2.4 Å, PDB ID 6DFZ). This structure is the first of any protein from coral of this genus. The occupancy of NAD across the four monomers of the tetrameric enzyme varies, allowing us to compare the response of the polypeptide structure to the presence of the stabilizing cofactor. We propose that these regions of difference represent areas of the protein important to its thermal stability.Support or Funding InformationNSF IOS‐1654249This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.