Crystal structure of firefly luciferase throws light on a superfamily of adenylate-forming enzymes
Key findings
The crystal structure of firefly luciferase was determined at 2.0 Å resolution with R-factor of 22.4% and free R-factor of 26.5%, resolving 523 out of 550 residues. The structure revealed two compact domains: a large N-terminal domain (residues 4-436) containing a β-barrel and two β-sheets in an αβαβα five-layered structure, and a small C-terminal domain (residues 440-544) forming a lid over the β-barrel. Conserved residues within the adenylate-forming enzyme superfamily are located on opposite sides of a wide cleft between domains, suggesting domain closure during catalysis.