1 research outputs found
Bioinspired Molecular Lantern: Tuning the Firefly Oxyluciferin Emission with Host–Guest Chemistry
Fireflies
generate flashes of visible light via luciferase-catalyzed
chemiexcitation of the substrate (luciferin) to the first excited
state of the emitter (oxyluciferin). Microenvironment effects are
often invoked to explain the effects of the luciferase active pocket
on the emission; however, the exceedingly complex spectrochemistry
and synthetic burdens have precluded elucidation of the nature of
these interactions. To decipher the effects of microenvironment on
the light emission, here the hydrophobic interior of cucurbit[7]Âuril
(CB7) is used to mimic the nonpolar active pocket of luciferase. The
hydrophobic interior of CB7 induces shifts of the ground-state p<i>K</i><sub>a</sub>s by 1.9–2.5 units to higher values.
Upon sequestration, the emission maxima of neutral firefly oxyluciferin
and its conjugate monodeprotonated base are blue-shifted by 40 and
39 nm, respectively, resulting in visual color changes of the emitted
light