In this article, we will discuss about the applications and classifications of bioluminescent bacteria. Bioluminescent bacteria are living organisms that emit light through a chemical reaction. They have diverse applications in biotechnology, pollution detection, and environmental monitoring, offering a sensitive and reliable tool for various fields.
Bioluminescent bacteria that are natural illuminators that produce light. They have discovered since 1000’s of years. Found in Indian subcontinent and Scandinavia. Aristotle and Darwin have also described phenomenon of oceans glowing. Bioluminescence in organisms have so many different purposes like defense, warning signals and attraction of mates but in case of bacteria it is mainly used for dispersal, quorum sensing, survival and persistence. https://pubmed.ncbi.nlm.nih.gov/9891783
It is a light produce in the result of a chemical reaction in a living organism that is a form of chemiluminescence in living organisms. Bioluminescence also called cold light as it is emitted from a body when its temperature is cold. This sort of radiation referred to as cold light. Light emitted from a body when it is hot is called incandescence. Cold light means less than 20% of the light generates thermal radiation, or heat.
It is a common phenomenon in many organisms of varying habitats. For example, terrestrial nematodes, fireflies, Ctenophores, marine vertebrates, Firefox fungi and so many other organisms including bacteria. It is interesting to note that many of these organisms are not bioluminescent by themselves, instead they provide home to bioluminescent bacteria inside or on the bodies to get benefit from bacterial bioluminescence.
CLASSIFICATION OF BIOLUMINESCENT BACTERIA:
1. LUMINESCENT BACTERIA:
They emit light in chemiluminescence reaction which enzyme catalyzed where luciferin pigment oxidized with the help of luciferase enzyme. They exist as symbionts within larger organisms such as Angler fish, jellyfish, clams etc.
They belong to the gram-negative genus and in the family Vibrionaceae. Members of this genus are bioluminescent. They are both psychrophiles and piezophiles. They exhibit fluorescence when in high density in a colony, otherwise free-living Photobacterium does not glow. Fluorescence is based on the accumulation of autoinducers which is proportional to cell density. A highly fluorescent prosthetic group separated from a Photobacterium phosphoreum through affinity chromatography.
3. ALIIVIBRIO FISCHERI:
They are gram negative rod shaped bacteria and has bioluminescent properties. It named after a German Microbiologist Bernhard Fischer and is key research organism for bacterial bioluminescence, quorum sensing and bacterial animal symbiosis. Its bioluminescence is also population dependent and it takes specific optimal density to activate lux operon. Its luminscense is brighter during the day and
dimmer during night time as required by camoflauge. It produces blue green light by action of luciferase enzyme which oxidises flavin mononucleotide and aldehyde by diatomic oxygen.
APPLICATIONS OF BIOLUMINESCENT BACTERIA:
This property used as a powerful tool in biotechnology for the visualisation, imaging, and control of biochemical processes. The firefly luciferase (FLuc) and D-luciferin system widely used in biochemical assays to determine ATP levels. It used for the sensing of a number of parameters, such as pH, concentration of metal ions, glucose etc. It is especially helpful for in vivo imaging of small mammals due to its superior sensitivity and specificity as a result of bioluminescence at molecular level.
2. POLLUTION DETECTION:
In the water environment, a luminescent bacteria bioassay proved beneficial .Photobacterium phosphorum T3 applied to determine the acute toxicity of water pollutants. Now bioluminescent bioassay is also proving significant in land pollution. Bluegreen luminescence can emitted in chlorophyllescent bacteria and the intensity of light remains constant under some steady conditions. When bacteria come into contact with a certain toxic substance, the light intensity of the luminescent bacteria reduced. In addition, the concentration of the toxicant correlated with the degree of inhibition. Vibrio fischeri, Photobacterium phosphorum, and Vibrio qinghaiensis are the three most commonly used luminescent bacteria in bioassay.
Bioluminescent bacteria possess unique capabilities for visualizing and controlling biochemical processes, making them valuable in biotechnology. Additionally, their sensitivity to pollutants enables their use in pollution detection and monitoring, providing a powerful tool for assessing environmental risks and aiding in remediation strategies.
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