Flight Studies on Photic Communication by the Firefly Photinus pyralis

Equilibrium intermediates in the reversible unfolding of firefly (Photinus pyralis) luciferase.

Firefly luciferase has been used as a model protein to study cotranslational and chaperone-assisted protein folding. We found conditions for reversible unfolding of luciferase in the absence of cellular factors, and we characterized denaturant-induced equilibrium unfolding transitions and refolding kinetics of the enzyme. Luciferase unfolding induced by guanidinium chloride at 10 degrees C can ...

Red light in chemiluminescence and yellow-green light in bioluminescence: color-tuning mechanism of firefly, Photinus pyralis, studied by the symmetry-adapted cluster-configuration interaction method.

The yellow-green luminescence from firefly luciferase has long been understood to be the emission from enol-oxyluciferin. However, a recent experiment showed that an oxyluciferin constrained to the keto form produced a yellow-green emission in luciferase (Branchini, B. R.; Murtiashaw, M. H.; Magyar, R. A.; Portier, N. C.; Ruggiero, M. C.; Stroh, J. G. J. Am. Chem. Soc. 2002, 124, 2112-2113). Th...

Mutagenesis of solvent-exposed amino acids in Photinus pyralis luciferase improves thermostability and pH-tolerance.

Firefly luciferase catalyses a two-step reaction, using ATP-Mg2+, firefly luciferin and molecular oxygen as substrates, leading to the efficient emission of yellow-green light. We report the identification of novel luciferase mutants which combine improved pH-tolerance and thermostability and that retain the specific activity of the wild-type enzyme. These were identified by the mutagenesis of ...

Development of a pH-Tolerant Thermostable Photinus pyralis Luciferase for Brighter In Vivo Imaging

A set of multicolored Photinus pyralis luciferase mutants for in vivo bioluminescence applications.

Error-prone PCR was used to isolate Photinus pyralis luciferase mutants producing bright light in the red-orange region of the spectrum. All mutations were clustered in the beta5-alpha10-beta6 region of N-terminal subdomain B and appear to affect bioluminescence color by modulating the position of the Ser314-Leu319 mobile loop with respect to the putative active site. Two red variants (Q283R an...