8/3/2019 Bio Luminescence is an Enchanting Process in Which Living Organisms Convert Chemical Energy Into Light

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Bioluminescence is an enchanting process in which living organisms convert chemical energy into light. With the interestingexception of the photoproteins, in most bioluminescence systems light results from the oxidation of an organic substrate, aluciferin, catalyzed by an enzyme called a luciferase. In nature, there is an amazing diversity of organisms that emit lightincluding bacteria, fungi, crustaceans, mollusks, fishes and insects. While the specific biochemistries of bioluminescence arediverse, all include an enzyme-mediated reaction between molecular oxygen and an organic substrate. It is likely too that allbioluminescence processes involve the formation and breakdown of a four-member ring peroxide or a linear hydroperoxide.

An overview of the chemical and mechanistic aspects of a major bioluminescence process, that of the bioluminescentbeetles, will be presented here.

Bioluminescence has thus far been reported in approximately 50 species of fungi, all of which are white-sporedbasidiomycetes traditionally placed in the family Tricholomataceae. Impressively, more than two thirds of thesebioluminescent species are members of the diverse and widespread genus Mycena. Additional genera containingluminescent species include Armillaria, Omphalotus (including Lampteromyces and luminescent Pleurotus species),Gerronema, Panellus and Dictyopanus (these latter two genera actually represent additional species of Mycena, but theyhave not yet been transferred to this genus). Luminescence, the intensity level and location of which varies by species,typically occurs in the mycelium and/or basidiomes, or some portion thereof. In Mycena lamprospora, however, it is themature spores rather than these tissues that have been observed to luminesce. In many instances it is the hyphae presentin decaying plant tissues that luminesces, resulting in the appearance of luminescent wood or leaves.

Fungal luminescence has been hypothesized to attract invertebrates that aid in spore dispersal, which may be a suitableexplanation for those species with luminescent basidiomes, but not for those in which only the mycelium emits light.

The Process of BioluminescenceBioluminescence is the result of a Biochemical reaction.It can also be described as a chemiluminescent reaction involving a direct conversion of chemical energy into light energy.

The reaction involves the following elements:· Enzymes (Luciferase) - biological catalysts that accelerate and control the rate of chemical reactions in cells.· Photons - packs of light energy.· ATP - adenosine triphosphate, the energy storing molecule of all living organisms.· Substrate (Luciferin) - a specific molecule that undergoes a chemical charge when affixed by an enzyme.· Oxygen - as a catalyst

A simplified formula of the bioluminescent reaction:

ATP(energy) + Luciferin (substrate)+ Luciferase(enzyme) + O2(oxidizer) → light (photons)

The bioluminescent reaction occurs in two basic stages:(1) The reaction involves a substrate (D-Luciferin), combining with ATP, and oxygen which is controlled by the enzyme(Luciferase). Luciferins and Luciferase differ chemically in different organisms but they all require molecular energy (ATP)for the reaction.(2) The chemical energy in stage one excites a specific molecule (The Luminescent Molecule: the combining of Luciferaseand Luciferin). The excitement is caused by the increased energy level of the luminescent molecule. The result of thisexcitement is decay which is manifested in the form of photon emissions, which produces the light. The light given off doesnot depend on light or other energy taken in by the organism and is just the bi-product of the chemical reaction and is

therefore cold light.The energy in photons can vary with the frequency (colour) of the light. Different types of substrates (Luciferins) inorganisms produce different colours. Marine organisms emit blue light, jellyfish emit green, fireflies emit greenish yellow,railroad worms emit red , and Glow worms and fungi emit blue-green light ( appears blue to the eye close up but is actuallyin the green light spectrum ).