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Bioluminescence . Julie Russell. What is it . Bioluminescence is a specific form of chemiluminescence in which the chemical energy that is produced in a chemical reaction is converted into radiant energy
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Bioluminescence Julie Russell
What is it • Bioluminescence is a specific form of chemiluminescence in which the chemical energy that is produced in a chemical reaction is converted into radiant energy • NOT fluorescence or phosphorescence, both of which do not involve a chemical reaction. • In bioluminescence or chemiluminescence the excitation energy is supplied by a chemical reaction rather than from a source of light. • Bioluminescence is primarily marine in nature and is the only source of light in the deep ocean. • Rarely occurs in fresh water • Ninety percent of deep-sea marine life is estimated to produce bioluminescence in one form or another. • Found throughout the spectrum of marine habitats, from the surface to the deep-sea floor.
How does it work? • Bioluminescence occurs only when two different compounds are in contact and, almost exclusively, when oxygen is present. The two compounds are luciferin, which produces the light, and luciferase, a protein that triggers and catalyzes the reaction. • The mechanism involves the loss of two electrons, also known as oxidation, by luciferin, a process achieved only through the intervention of luciferase to yield oxyluciferin. • Sometimes the luciferin and catalyzing protein (the equivalent of a luciferase), as well as a co-factor such as oxygen, are bound together to form a single unit called a "photoprotein." This molecule can be triggered to produce light when a particular type of ion is added to the system (frequently calcium). • Adenosine triphosphate (ATP) is involved in most instances • The chemical reaction can occur either within or outside of the cell.
How Does It Work? • The luciferase catalyzes the oxidation of luciferin • Resulting in light and an inactive "oxyluciferin" • In most cases, fresh luciferin must be brought into the system, either through the diet or by internal synthesis.
Luciferin • Luciferin is the basic substrate of any bioluminescent reaction. • Bacterial luciferin is a reduced riboflavin phosphate which is oxidized in association with a long-chain aldehyde, oxygen, and a luciferase. • At pH 8 the molecule is "protected" from the luciferase by a "luciferin-binding protein", but when the pH lowers to around 6, the free luciferin reacts and light is produced. • A modified form of this luciferin is also found in herbivorous euphausiid shrimp, perhaps indicating a dietary link for the acquisition of luciferin.
Luciferin • Vargulin or Cypridina-type luciferin is found in the ostracod ("seed shrimp") Vargula and Cypridina, and is also used by the midshipman fish Porichthys. Here there is a clear dietary link, with fish losing their ability to luminesce until they are fed with luciferin-bearing food. It has been shown that ostracods synthesize this molecule from the amino acids tryptophan, isoleucine, and arginine. • Coelenterazine is the most "popular" of the marine luciferins, found in a variety of phyla. This molecule can occur in luciferin-luciferase systems, and is famous for being the light emitter of the photoprotein "aequorin". • Although there are hundreds of types of luminous animals in the sea, there are surprisingly few basic luciferins (light emitters) which have been found in across many species • In some cases this conservation can be explained by animals acquiring luciferin through the food chain, but in other cases organisms have been shown to have the ability to synthesize the same chemical on their own.
Purpose • Serves two or more purposes • Can be both offensive and defensive within same organism • Mate attraction • Species Recognition • Many functions are unknown due to lack of experimental evidence
Evolution • Has evolved independently at least 40 times • Bioluminescent organisms include ctenophores, annelid worms, mollusks, insects, and fish. • Luciferinis thought to derive from the similarly structured chlorophyll, which is found in most plants. The molecule is protected from luciferase at slightly basic medium by a luciferin-binding protein. However, once the acidity increases, the free luciferin reacts, and light is emitted. • The light produced by a single dinoflagellate is only six to eight photons in energy, and the flashing may last only one-tenth of a second. Larger organisms, such as jellyfish provide flashes that may last up to tens of seconds. • The disappearance of the flash, once oxygen is consumed, has suggested that the bioluminescent reaction was originally used to remove toxic oxygen from primitive types of bacteria that developed at a time when oxygen was not available.
Emitted Light • Most organisms emit between 440 nm and 479 nm. • Some cnidarians have green fluorescent proteins that absorb an initially blue emission and emit it shifted towards the green (~505 nm). • Measurements at various depths confirm emission clustering in the blue to green region of the spectrum. • Most dinoflagellates emit about 6e8 photons in a flash lasting only about 0.1 second. Much larger organisms such as jellyfish emit about 2e11 photons per second for sometimes tens of seconds. • The intensity of luminescence by photosynthetic dinoflagellates is strongly influenced by the intensity of sunlight the previous day. The brighter the sunlight the brighter the flash. • Some organisms emit light continuously, but most emit flashes of durations ranging from about 0.1 s to 10 s. • Certain loose jawed fish emit red and infrared light
How is it triggered? • three types of stimuli can cause bioluminescence in dinoflagellates: mechanical, chemical, and temperature stimulation • Mechanical forms of stimulation, such as the stirring of water from a moving boat, a swimming fish, or a breaking wave, are prevalent in many Pyrrhophyta. The light appears to serve as a “burglar alarm” against grazing predators, which are then being seen through the flash by a larger second predator • Temperature lowering in some dinoflagellate species also creates bioluminescence. • In most multicellular species luminescence is neural controlled. Thus in some fish the sympathetic nervous system controls luminescence by way of the neurotransmitter nor-adrenaline
How is it triggered? • In single cell organisms like dinoflagellates or radiolarians luminescence is triggered by deformation of the cell surface by minute forces(1 dyne per square cm). • Mechanical deformation causes an action potential sweeping over the vacuole membrane and this is thought to induce light emission by admitting protons from the acidic vacuole into contact with the cellular elements that contain the light emission chemistry. • In some instances in marine invertebrates with eyes or other light receptors, light emission can be induced by photic excitation, even by another luminescing organism. Called "empathetic" luminescence, this phenomenon has as yet undemonstrated potential to enhance the luminescence generated by a moving source by photic transfer from the luminescent organisms mechanically triggered by the moving source
What is produced? • Red Tides (dinoflagellates) • Milky Seas -where huge populations of bacteria give the ocean an eerie glow. • A squid which changes the color of its luminescence to match moonlight and sunlight. • · A siphonophorewhich uses red light to lure fish to its tentacles. • Tiny single-celled dinoflagellates that make the sea sparkle • Fishes like Malacosteusand Aristostomiaswith their own “night vision" light. • Crustaceans which send out coded messages to their own species when it is time to mate.
Use in Science • The chemical reactions that lead to bioluminescence release energy in the form of light. A bioluminescent reaction is 100 percent efficient and converts all the emitted energy into light. Because there is no heat released, bioluminescence is also known as “cold light.” • Bioluminescence has also played a crucial role in the direct studies of several cellular and biochemical processes, such as in the formation of ultimate carcinogens from benzoapyrene. • Calcium levels are monitored via the jellyfish biochemical system, adenosine triphosphate (ATP) measurements are achieved through the firefly, and the gene activity of organisms can be detected by splicing known bioluminescent proteins
Use In Science • Despite its common presence, bioluminescent remains difficult to study. This reason is that organisms must be captured in good condition to witness their bioluminescent behavior. Nets and grab-type samplers are too indiscriminate to obtain healthy specimens from the deep ocean floor a kilometer (about 3/5 mile) below the surface • The methods used to study bioluminescence include low-light photography, fluorescence microscopy, and spectrometry (the measure of wavelengths), along with chemical and genetic analyses of the light-producing chemicals involved
Fire Fly squid • AKA Sparkling Enope Squid • Wataseniascintillans • About 3 ines • Western Pacific Ocean • Found at depth of 600-1,200 ft. • Flashing lights that resemble fire flies • Light produces organs : photophores • Emit blue light • Can create light patterns • Used for • Communication with mates • Disguise shape and confuse predators • Believed to have colored vision • Predator • Lights attract prey
Comb jelly • Feeds by pumping water intos body cavity using it cilias. • Feeds on zooplankton • Can tolerate broad range of water temperature, salinity, and pollution • Bioluminescence is used for protection • AKA Sea Walnut, Warty comb jelly • About 4 in • Visible internal structures • Externally 8 longitudinal rows of cilia • 8 segments • Cilia movement created bright fluorescent stripes on the body • Soft green or blue green may be seen at night.
Dragonfish • Barbel attached to chin • Light producing • Used as fishing lure • Flashes on and off and waves back and forth • Photophores along sides of body • Attract and disorient prey • AKA: Scaleless Dragon • Grammatostomiasflagellibarba • 4-6 in • Tropical ocean regions • Depth of down to 5,000 ft • Light produced my photophore • Light used to attract prey in dark waters • Signal potential mates
Work Cited • "Bioluminescence." ScienceDaily. ScienceDaily, n.d. Web. 26 Apr. 2014. <http://www.sciencedaily.com/articles/b/bioluminescence.htm>. • Ghayourmanesh, Soraya. "Bioluminescence." Salem Press Encyclopedia Of Science (2013): Research Starters. Web. 26 Apr. 2014 • Haddock, Steve. "Bioluminescence." Ocean Explorer. NOAA National Oceanic and AtmosphereicAdmistation, 2009. Web. 26 Apr. 2014. <http://oceanexplorer.noaa.gov/explorations/09bioluminescence/background/bioluminescence/bioluminescence.html>. • "The Bioluminescence Web Page." The Bioluminescence Web Page. UCSB, 25 Mar. 2014. Web. 26 Apr. 2014. <http://biolum.eemb.ucsb.edu/>. • "The Sea." The Sea. N.p., 2013. Web. 26 Apr. 2014. <http://www.seasky.org/sea.html>.