Bioluminescence Bioluminescence BIO means LIFE Luminescence means LIGHT
Bioluminescence
Bioluminescence BIO means LIFE Luminescence means LIGHT Can you guess what Bioluminescence means? ? Bioluminescence is defined as the production and the emission of light by a living organism.
Chemical Reaction Bioluminescence occurs when an electron Click to edit the outline receives sufficient energytext from an external format source to drive the electron an excited Second Outline Level higher energy state. At this point, the Third Outline system is unstable. When the electron Level returns to the lower state, energy is given Fourth Outline off in the form of a photon. Level Fifth Outline Level Sixth
Chemical Reaction Three requirements for reaction to proceed: 1) Light emitting organic molecule – Typically Luciferin 2) Source of Oxygen 3) Protein Catalyst – Typically Luciferase
Photoproteins • • Sometimes the three required components for biolumenescence are bound together into a complex called a Photoproteins are not involved in luciferinluciferase reaction. Instead photoproteins utilizes an organic light emitting molecule and a cofactor. The total amount of light emitted is porportional to the size of the photoproein
Photoproteins Click to edit the outline The jellyfish, Aequorea, uses a photoprotein. text format Instead of a protein Second Outline Level catalyst, the jellyfish Third Outline Level emits light when the cofactor Ca 2+ is Fourth Outline Level introduced into the Fifth system. Outline Level Sixth
Fluorescent Proteins • • Click to edit the outline Sometimes, there is a fluorescent protein format that absorbs the light and text remits the light at longer wavelengths. Second Outline Level Third Outline Examples include Green Fluorescent Proteins Level and Phycobiliproteins. Fourth Outline Level Fifth Outline Level Sixth
Green Fluorescent Proteins • • Amino acids in the 66 th and 67 th position emit fluorescence of wavelengths around 510 nm The GFP gene Click to edit the outline text format Second Outline Level Third Outline Level Fourth Outline Level Fifth Outline Level Sixth
Phycobiliproteins • • Phycobiliproteins occur naturally in algae and bacteria and contain a covalently linked fluorescence group The wavelength of light emitted from these proteins is between 575 nm and 660 nm
Examples in Nature • • Diatoms are marine phytoplankton that emit blue -green fluorescence. That creates the “glowing” blue waves below. These diatoms are actually used in street paint for the glowing properties.
Examples in Nature • While terrestrial biolumenescence is less common, they do still exist. Examples include fireflies and a type of fungus called foxfire.
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