Bioluminescence is the ability of a living organism to emit light; a phenomenon which has intrigued humans for thousands of years and allowed them to invent mystical and magical stories behind these beacons of light. We might have decided that these lights serve a magical purpose, but evolution has found many uses for this process from protection, all the way to communication. The chemical mechanism behind these bioluminesent photons is a very simple one, though not the same in all organisms, they share some of the same basic principles. Taking the firefly as an example, the compound which acts as it's light bulb is called
luciferin, and the reaction begins with molecular oxygen and ATP, with the help of the enzyme
luciferase, turning luciferin into a
dioxetane derivative (mechanism of this can be seen
here)
1.
Once this dioxetane derivative is formed the emission of light reaction is ready to occur spontaneously. This happens in a concerted reaction releasing CO
2 and producing an excited ketone. The electron of the excited ketone then falls in energy to create a photon and end with the final product of oxyluciferin.
The newly created oxyluciferin is then enzymatically recycled into luficerin by this mechanism
here2.
References:
1. Aldo Roda Chemiluminescence and Bioluminescence: Past, Present and Future, p. 57, Royal Society of Chemistry, 2010, ISBN 1-84755-812-7
2. Keiko Gomi and Naoki Kajiyama. Oxyluciferin, a Luminescence Product of Firefly Luciferase, Is Enzymatically Regenerated into Luciferin. J. Biol. Chem. 2001 276: 36508-36513. July 16, 2001, doi:10.1074/jbc.M105528200
Responding method for act again, re-act. Responding is depending on what we already know and often so well that we do it instantly. Some responses are very useful for our success, like taking our send from a hot heater or moving away from an onset car. In other terms when our systems feeling risk we respond without considering. This response is all very well in urgent circumstances, but the associate in our connection may end the connection very easily without our even being conscious that our responses are automated and reverse to our best attention React to an act
ReplyDeleteResponding method for act again, re-act. Responding is depending on what we already know and often so well that we do it instantly. Some responses are very useful for our success, like taking our send from a hot heater or moving away from an onset car. In other terms when our systems feeling risk we respond without considering. This response is all very well in urgent circumstances, but the associate in our connection may end the connection very easily without our even being conscious that our responses are automated and reverse to our best attention React to an act
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