BIOLUMINESCENCE IN MARINE LIFE SARTHAK BASAK UG STUDENT, 5TH SEMESTER, DEPARTMENT OF ZOOLOGY, SETH ANANDRAM JAIPURIA COLLEGE, KOLKATA ABSTRACT : Bioluminescence spans all oceanic dimensions and has evolved many times — from bacteria to fish — to powerfully influence behavioral and ecosystem dynamics. Marine organisms utilize bioluminescence for vital functions ranging from defense to reproduction. Animals can closely control when they light up by regulating their chemistry and brain processes depending on their immediate needs, whether a meal or a mate. New methods and technology have brought great advances in understanding of the molecular and chemical basis of bioluminescence, its physiological control, and its significance in marine communities. Bioluminescence is a ‘cold light’. Cold light means less than 20% of the light generates thermal radiation, or heat. Most marine bioluminescence, for instance, is expressed in the blue-green part of the visible light spectrum. These colors are more easily visible in the deep ocean. Bioluminescent organisms are a target for many areas of research. They have been used in popular culture as well. It has been quite fascinating for me to find out why humans cannot glow like the adorable fireflies observed in an open field at night or a colourful jellyfish under the deep ocean. The aim of the review is to know and share the information about the wonderful creatures at the bottom of the ocean, who combat with their dark surroundings by their extraordinary capability of producing light.
HOW IT HAPPENS ?
WHAT IS BIOLUMINESCENCE ? • Production and emission of light by a living organism in the form of chemiluminescence. In this
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process, chemical energy is converted into light energy. Occurs widely in marine vertebrates and invertebrates, as well as in some fungi, microorganisms and terrestrial arthropods such as fireflies. In some animals, the light is bacteriogenic, produced by symbiotic bacteria. In 1920, the American zoologist E. Newton Harvey summarized early work on bioluminescence. The French pharmacologist Raphaël Dubois also carried out some works on bioluminescenc Charles Darwin also observed a luminous jelly-fish in the sea, showing bioluminescence.
E. Newton Harvey
DIFFERENT BIOLUMINESCENT ORGANISMS A. BACTERIA • In bacteria, two simple substrates [a reduced flavin mononucleotide (FMNH2 ) and a longchain aliphatic aldehyde (RCHO)] are oxidized by molecular oxygen and luciferase. • Among prokaryotes, light production is known only from the so-called eubacteria, specifically Gram-negative γ-proteobacteria. • Found in temperate to warmer waters generally. Bacteria are not luminous until they have reached sufficiently high concentrations to initiate quorum sensing.
Bioluminescence is a product of chemical reactions in an organism. • Three ingredients are needed for bioluminescence to occur: 1. Luciferin: light producing substance. 2. Luciferase: enzyme. 3. Oxygen: colourless and odourless gas. • In the presence of oxygen, enzyme luciferase* acts upon luiferin to produce energy. • This energy takes the form of light. The oxydized luciferin becomes inactive oxy-luciferin. *Some reaction do not involve luciferase enzyme so the reaction involve a chemical Photoprotein, which combines with oxygen and luciferase. •
Fig.: Bioluminescent bacteria
B. DINOFLAGELLATES • They are the most commonly encountered bioluminescent organism in marine life. • They produce the ‘bioluminescent bays’ which are tourist destinations in Puerto Rico and Jamaica. • The chemical structure of dinoflagellate luciferin are similar to chlorophyll. In large numbers, some species may form potentially toxic red tides. Fig.: Bioluminescent dinoflagellate
C. MUSHROOMS • ‘Fox fire’ refers to the green glow light emitted by wood decaying mushrooms and other fungus. • Earlier it was used as a light source in wooden submarine. • They use luciferin illudin for bioluminescence, which is toxic to ingest. D. JELLYFISHES AND COMB JELLIES Fig.: Mycena lampadis • Most jellyfish bioluminescence is for defence. Jellyfish such as comb jelly produce bright flashes to startle a predator. • Others such as siphonophores produce chain of light or release thousands of growing particles as a mimic of small plankton to confuse the predator. • Some jellyfish can release their tentacles as glowing decoys. Some produce glowing slime that can stick to a potential predators to make them vulnerable to predation.
Fig.: Bioluminescent jellyfish
Fig.: Bioluminescent comb jelly
Fig.: Bioluminescent siphonophore
E. ANNELIDS • Female polychaets produce luminescent secretions that attract the males to swarm around them. • Several benthic scale-worms (Polynoidae) emit light using an unknown protein triggered with superoxide radicals.
USES OF BIOLUMINESCENCE
Fig.: Odontosyllis enopla
F. CRUSTACEANS • Many types of planktonic crustaceans use species specific luciferases for different types of luciferins. • Some of them have light organs along the lower surface of body, which they use for counterillumination, some also have two small light organs on their eyestalks.
Fig.: Bioluminescent shrimp species
G. MOLLUSCS • Luminous marine molluscs include a few unusual gastropods. One of the longest-known and best studied luminous molluscs is the bivalve Pholas. • The most prominent of the bioluminescent marine molluscs are the cephalopods. Squids, though, have intrinsic bioluminescence, using a luciferin along with their individual luciferase. • Light organs cover the ventral mantle with bright organs near the eyes and at the tips of the arms— typical for many other kinds of squids. Fig.: Bioluminescent squid
H. ECHINODERMS • Major groups of echinoderms– brittle stars (Ophiuroidea), sea stars (Asteroidea), sea cucumbers (Holothuroidea) are bioluminescent. • A complex system of neurotransmitters modulates light output in these groups, and light originates from both an unknown photoprotein depending on the species.
Fig.: Larval leaf scorpion fish www.pos te rs e ss io n.com
Fig. The distribution of bioluminescence emission maxima varies by marine environment and organism type. Bioluminescent emissions extend over the full visible range
• Bioluminescence plays an important role in the ecology of the ocean. The function of bioluminescence in the ocean is clearly understood in the context of the essentially dark environment below 200 m. The functions of bioluminescence are: 1. Defence or self-protection 2. Schooling of fishes Feeding (finding or attract the prey). 3. Communication (in the dark) Mating 4. Mimicry
APPLICATION OF BIOLUMINESCENCE IN BIOTECHNOLOGY • Monitoring of biological processes (e.g. Gene expression, protein-protein interaction) with clinical and diagnostic and drug discovery application. • University of Wisconsin-Madison is researching the use of genetically engineered bioluminescent E.coli bacteria in a light bulb. • Underwater Bioluminescence Assessment Tool (UBAT) is designed to provide measurement of mechanically stimulated bioluminescence potential.
CONCLUSION • Bioluminescence is widespread across most forms of marine life. Light emitters (Luciferin) are conserved, while enzymes (luciferase) are diverse and species-specific. • Because a large fraction of animals is bioluminescent, quantifying luminescence can provide a proxy for heterotrophic biomass. The distribution of bioluminescent organisms can be measured by automated instruments and is a useful parameter for understanding ocean ecology. Fig.: Bioluminescent brittle star
Fig.: Bioluminescent sea star
Fig.: Bioluminescent holothuroid
I. FISHES • Found in at least 42 families across 11 orders of bony fishes, in addition to one family of sharks. • The tally of luminescent fishes represents about 8% of the approximately 20,000 known species. • Most of the bioluminescent fishes are marine in nature; freshwater contains the smallest number of bioluminescent species. • e.g. Anglerfish, Ponyfish, Hatchetfish, Dragonfish, Malacosteus, Diaphus etc.
REFERENCE 1. Herring P.J., Widder E.A., in Encyclopedia of Ocean Science, Vol. 1 (Academic Press, San Diego, CA, 2001), pp. 308–317. 2. Meighen E.A., Molecular biology of bacterial bioluminescence, Microbiol Rev. 55 (1991) pp. 123– 142. 3. Widder E.A., Bioluminescence in the Ocean: Origins of Biological, Chemical, and Ecological Diversity, Vol. 328 (2010), pp. 704–708. 4. https://oceanservice.noaa.gov/facts/biolum.html 5. https://www.nationalgeographic.com/animals/reference/bioluminescence-animals-oceanglowing/ 6. https://www.slideshare.net/saniabibi/bioluminescence-ppt ACKNOWLEDGEMENT Principal and all the faculty members of Department of Zoology, Seth Anandram Jaipuria College, Kolkata. www.postersession.com