Bioluminescence

Great firefly ( Lampyris noctiluca )

As bioluminescence ( Greek βιός BIOS 'and' Life in Latin lumen , light ') is in biology refers to the ability of living organisms, or with the help of symbionts to produce light. In the case of highly organized organisms, light is often generated in special luminous organs , in eukaryotic single cells in special organelles and in bacteria in the cytoplasm . It is based on chemical processes in which released energy is given off in the form of light, so it is chemiluminescence . A distinction is made in bioluminescence between primary and secondary lighting . The normal case is the primary glow in which an animal is able to glow by itself. If the glow is caused instead by symbiotic bacteria, such as B. known from fish, one speaks of secondary glow.

Biological function

Bioluminescence can have several functions:

Attracting prey or partners
communication
Warning or threatening function
Deterrent or distraction function
Camouflage by adapting your own light to the light of the surroundings

distribution

Bioluminescent species exist in almost all realms of organisms , but not among higher plants and terrestrial vertebrates .

Spread of bioluminescence
rich	primary or secondary glow
Animals (multiple tribes )	primary glow ( only secondary glow in vertebrates )
Mushrooms (few species)	primary glow
higher plants	no glow
Protozoa (some)	primary glow
Bacteria (few)	primary glow

Animals

Photinus pyralis in flight

Insect bioluminescence with, for example firefly (firefly; Lampyridae) and luminescent beetle (genera Cucujo and Pyrophorus ). There are also glowing collembola (springtails).

Light organs of the deep-sea fish Photostomias guernei (behind the eye)

Bioluminescence is particularly widespread among marine life, especially in the deep sea (up to 90 percent of deep sea organisms), but also in coastal waters (around five percent). Various cephalopods such as Vampire squid ( Vampyroteuthis infernalis ), the magic lamps ( Lycoteuthis ) and other squid (Teuthida) euphausiid ( krill , Euphausiacea), luminescent jellyfish ( luminescent jellyfish Pelagia noctiluca , Aequorea victoria , helmet jellyfish Periphylla periphylla ), polychaete ( Polychaeta ) as Eusyllis blomstrandi in the Helgoland Felswatt ( Helgoland ), the Chaetopterus variopedatus , which lives hidden in the sand, and the free-swimming Tomopteris helgolandica , corals such as Renilla reniformis and various deep-sea fish . Among the nudibranchia , sea-living nudibranchs, there are also several bioluminescent species, such as B. Plocamopherus imperialis and Phylliroe bucephalum .

Mushrooms

Mycena chlorophos in the Hachijojima Botanical Garden

Out of over 100,000 species of fungus examined, only 71 are bioluminescent. These include the honey-yellow honey mushroom ( Armillaria mellea ), the luminous olive mushroom ( Omphalotus olearius ) and some species of the genera dwarf balls ( Panellus , e.g. Panellus stipticus ), side mushrooms ( Pleurotus , e.g. Pleurotus japonicus ) and helmets ( Mycena , e.g. Mycena citricolor , Mycena lux-coeli ).

Bioluminescence developed in four lines of descent. It could be shown that the bioluminescent phenomena are based on the same principles in all four lineages.

Unicellular organisms

Dinoflagellate bioluminescence caused by breaking the waves

The so-called sea glow is caused by plankton , for example by unicellular dinoflagellates ( Noctiluca scintillans ), which react to changes in flow by emitting light. Sea lights can be observed on numerous coasts.

bacteria

There are some luminescent bacteria living free in seawater , which can also be found on foods such as fish, meat and eggs. These include, for example, Aliivibrio fischeri and photobacteria . Aliivibrio fischeri reproduces on dead saltwater fish and can be easily observed if a dead, fresh salted herring is kept cool for some time, which then glows in the dark.

There are also symbiotically living luminescent bacteria that occur in special organs of marine animals; Frogfish and lantern fish in particular live in symbiosis with luminous bacteria.

generation

A distinction is made between two forms of bioluminescence: primary and secondary glow. It is called primary glow when the organism generates the luminescence itself. Secondary glow, on the other hand, is when an organism enters into a symbiosis with other living beings (e.g. with luminescent bacteria) that have the ability to primary glow.

Symbioses

There are often symbioses of animals with luminous bacteria. The bacteria are supplied with food and oxygen by their hosts and often live in special skin pockets or parts of the body. An example are the deep sea angler fish .

Luciferin / luciferase

A frequently used bioluminescent chemical reaction is the exergonic oxidation of luciferins as D luciferin with molecular oxygen (O ₂ ), catalyzed by enzymes of the luciferases . This creates dioxetanes or dioxetanones , which break down with the release of carbon dioxide and release the stored energy in the form of light.

Both the luciferins and the luciferases are species or group-specific, that is, characteristic of each group of organisms. The luciferases evidently emerged from other enzymes, the oxygenases , in the course of evolution . The change, mostly the splitting off of subgroups on the luciferin, creates energy that is emitted as a light quantum .

Aequorin / coelenterazine / coelenteramide

Aequorin catalyzes the oxidation of coelenterazine (left) to coelenteramide ; when an energy-rich intermediate stage decays, light is created.

Another way of generating light, namely photoproteins, is used by the jellyfish Aequorea victoria . This coelenterate ( hollow animal ) uses aequorin , a Ca ²⁺ -dependent primary photoprotein. Since it is not chemically converted in the course of the reaction like other luciferins , but returns to its original state after the emission of light, it can be reused indefinitely. The blue-green glow of these jellyfish is caused by the combination of aequorin with the green fluorescent protein (GFP), which is now also used as an integral part of (cell) biological research.

Foxfire bioluminescence

Fungi use Foxfire bioluminescence , whereby the enzyme superoxide dismutase (SOD) leads to the generation of bioluminescence.

application

Bioluminescence is not only of interest for basic research. Various technical applications of bioluminescence have been used routinely for some time. For example, bioluminescence is used as a low-risk labeling method in molecular biology , which together with fluorescent labeling has largely replaced the radioactive labeling method . Bioluminescence is also used as a detection method in ecotoxicology to detect and quantify toxins. The use of dinoflagellates in flow research to detect turbulence is discussed. Some researchers are already announcing self-illuminating monitors based on bioluminescence.

In 1999 British newspapers - and then media in other countries - reported on alleged work on self-illuminating Christmas trees. However, this never existed.

In the recent past, the bio-engineers at the US company BioGlow have succeeded in growing an autoluminescent plant with the help of genetic manipulation and bioluminescent enzymes. The aim of the development was to generate a clean, sustainable and affordable vegetable alternative for light sources. This new property of the plant is achieved by integrating marine bacteria into the chloroplast genome of the ornamental tobacco species Nicotiana alata . These naturally produce light as part of their induced metabolism.

literature

Osamu Shimomura : Bioluminescence. Chemical Principles and Methods . Word Scientific Publishing Company, New Jersey 2006, ISBN 981-256-801-8 .
EA Aries: Bioluminescence in the ocean. Origins of biological, chemical, and ecological diversity . In: Science . tape 328 , no. 5979 , May 7, 2010, p. 704-708 , doi : 10.1126 / science.1174269 , PMID 20448176 .
Aldo Roda (Ed.): Chemiluminescence and Bioluminescence. Past, Present and Future . RSC Publishing, Cambridge 2011, ISBN 978-1-84755-812-1 .
Thérèse Wilson, J. Woodland Hastings: Bioluminescence. Living Lights, Lights for Living . Harvard University Press, Cambridge (Massachusetts) 2013, ISBN 978-0-674-06716-5 .

Individual evidence

↑ Bill Rudman: Plocamopherus imperialis. In: seaslugforum.net. Australian Museum, Sydney, December 21, 1998; Retrieved July 17, 2016 .
↑ Bill Rudman: Phylliroe bucephalum. In: seaslugforum.net. Australian Museum, Sydney, August 9, 2000; Retrieved July 17, 2016 .
↑ ^a ^b Osamu Shimomura : The role of superoxide dismutase in regulating the light emission of luminescent fungi . In: Journal of Experimental Botany . tape 43 , no. 11 , 1992, pp. 1519–1525 , doi : 10.1093 / jxb / 43.11.1519 .
↑ Anderson G. Oliveira, Dennis E. Desjardin, Brian A. Perry, Cassius V. Stevani: Evidence that a single bioluminescent system is shared by all known bioluminescent fungal lineages . In: Photochemical & Photobiological Sciences . tape 11 , no. 5 , 2012, p. 848-852 , doi : 10.1039 / C2PP25032B .
↑ Jonathan M. Kendall, Michael N. Badminton: Aequorea victoria bioluminescence moves into an exciting new era . In: Trends in Biotechnology . tape 16 , no. 5 , May 1998, pp. 216-224 , doi : 10.1016 / S0167-7799 (98) 01184-6 , PMID 9621461 .
↑ Dennis E. Desjardin, Anderson G. Oliveira, Cassius V. Stevani: Fungi bioluminescence revisited . In: Photochemical & Photobiological Sciences . tape 7 , no. 2 , January 2008, p. 170-182 , doi : 10.1039 / B713328F .
↑ Genetically modified Christmas tree would glow. In: BBC News. October 25, 1999, accessed July 17, 2016 .
↑ Marcel Robischon: Green Glow and Fantasy. Stories of Genetically Engineered Christmas Trees . In: Christmas Trees . January 2006, ISSN 0199-0217 , OCLC 1711451 , p. 23-26 .
↑ Starlight Avatar. BioGlow, archived from the original on April 14, 2016 ; Retrieved July 17, 2016 .