The structural origin and biological function of pH-sensitivity in firefly luciferases
Nenhuma Miniatura disponível
Data
2008-02-19
Autores
Viviani, V. R.
Arnoldi, F. G C [UNESP]
Neto, A. J S [UNESP]
Oehlmeyer, T. L. [UNESP]
Bechara, E. J H
Ohmiya, Y.
Título da Revista
ISSN da Revista
Título de Volume
Editor
Resumo
Firefly luciferases are called pH-sensitive because their bioluminescence spectra display a typical red-shift at acidic pH, higher temperatures, and in the presence of heavy metal cations, whereas other beetle luciferases (click beetles and railroadworms) do not, and for this reason they are called pH-insensitive. Despite many studies on firefly luciferases, the origin of pH-sensitivity is far from being understood. This subject is revised in view of recent results. Some substitutions of amino-acid residues influencing pH-sensitivity in firefly luciferases have been identified. Sequence comparison, site-directed mutagenesis and modeling studies have shown a set of residues differing between pH-sensitive and pH-insensitive luciferases which affect bioluminescence colors. Some substitutions dramatically affecting bioluminescence colors in both groups of luciferases are clustered in the loop between residues 223-235 (Photinus pyralis sequence). A network of hydrogen bonds and salt bridges involving the residues N229-S284-E311-R337 was found to be important for affecting bioluminescence colors. It is suggested that these structural elements may affect the benzothiazolyl side of the luciferin-binding site affecting bioluminescence colors. Experimental evidence suggest that the residual red light emission in pH-sensitive luciferases could be a vestige that may have biological importance in some firefly species. Furthermore, the potential utility of pH-sensitivity for intracellular biosensing applications is considered. © The Royal Society of Chemistry and Owner Societies.
Descrição
Palavras-chave
benzothiazole derivative, firefly luciferase, heavy metal, luciferase, luciferin, amino acid sequence, amino acid substitution, beetle, binding site, bioluminescence, enzyme structure, high temperature, hydrogen bond, molecular model, pH, priority journal, red light, review, site directed mutagenesis, Amino Acid Sequence, Animals, Evolution, Fireflies, Hydrogen-Ion Concentration, Luciferases, Luminescence, Models, Molecular, Molecular Sequence Data, Protein Conformation, Sequence Homology, Amino Acid, Coleoptera, Elateridae, Photinus pyralis
Como citar
Photochemical and Photobiological Sciences, v. 7, n. 2, p. 159-169, 2008.