Nicholas T.

If you have ever seen a firefly or Finding Nemo, you have already witnessed bioluminescence.

Bioluminescence is the light created from certain chemical reactions called chemiluminescence within an organism. Bioluminsecence is not as rare as you would think. It occurs in various organisms, primarily, but not limited to, marine species, such as fish and jellies, but also on land with species such as fireflies and foxfire. However, there is a lot more to it than just glowing.

The Chemistry Behind Bioluminescence
There are two chemicals required for bioluminescence: luciferin and luciferase (or a photoprotein). Luciferin is the chemical that creates the light and luciferase is the catalyst (driving force) of the reaction.

  1. Luciferin oxidizes with the help of luciferase as a catalyst
    Luciferin-Luciferase Reaction
    Luciferin-Luciferase Reaction
  2. This reaction yields oxyluciferin and LIGHT
  3. Oxyluciferin is flushed out and new luciferin is brought back in to restart the chemical reaction

New luciferin is created either by synthesis or by absorbing it as food. Many of marine organisms have bioluminescent bacteria within them where they can get luciferin from.

Luciferase is an enzyme that quickens the rate of the reaction, also known as a catalyst. Since it is a catalyst, it is not used up during the reaction and therefore does not need to be replenished like the substrate, luciferin.

The color that an organism can bioluminesce depends on the luciferin molecules. There are many types of luciferins. Each different luciferin system varies from each other as seen below in the table. However, each will billuminesce reagardless of type when interacted with luciferase.
Bacterial luciferin
external image bacteria2.gif
Vargula luciferin
external image vargulin.gif
Dinoflagellates luciferin
external image dino.luciferin.gif
Coelenterazine luciferin
external image coelenterazine.gif

Firefly luciferin
external image firefly.gif

On occasion, luciferin, oxygen, and a single protein called a Photoprotein react. These reaction do not need an enzyme such as luciferase. However, the three also need certain ions such as calcium to make light. Photoproteins are commonly found in crystal jellies. The GFP (green fluorescent protein) has redefined fluorescent microscopy research, which can be used to tag cells to study their structure and movement. Another use of GFP is to create GloFish and even glowing rats.

Bioluminescence is often confused with fluorescence. Fluorescence is not the same because there is not chemical reaction. Energy is absorbed from a light then remitted instead. The energy for bioluminescence energy is supplied by a chemical reaction instead of light.

Bioluminescence Lights and Uses for Organisms
(Click on pictures pour voir plus de photos)

Most light from bioluminescene comes in flashes that last less than a second. Only few organisms can emit light constantly.

Bioluminescent marine organisms often emit blue-green colors. These colors are simply more visible. Hatchetfish uses bioluminescence to its advantage to mask its true shape to beffudle predators.

Firefly Squid
Firefly Squid
Comb Jelly
Comb Jelly

On land, bioluminescent organism also give off blue-green colors with the addition of yellow. Most can only emmit a single color, but railroad worms can glow in multiple colors simultaneously. This is due to different types of luciferase present in the worm.
Foxfire Fungi
Foxfire Fungi
Railroad Worm
Railroad Worm

Bioliminescence: Applied into the Real World

Researchers in the agricultural industry are implementing bioluminescent genes into crops. The plants will glow to alert farmers when they need nutrients or even when they are diseased.

Candy is a common commodity that BioLume wants to light up. BioLume cloned the enzymes from marine animals. Oxygen and an aqueous solution, such as saliva, will activate the reaction to make lollipops glow.
external image Wired%20Lolly%20078new.jpg

Streetlights drain energy and students at the University of Cambridge are researching was to replace these energy drainers. Genes from fireflies would be spliced into trees. The trees will absorb light during the day and store it to have energy to glow in the night. These could potential help streetlights.
external image bioluminescence-02-1111-mdn.jpg
Marine bacterium can be used to evaluate water. This bacteria will glow brighter with certain toxic chemicals because they react with them by creating light.
external image bioluminescence-04-1111-mdn.jpg
Bioluminescence can be used to see biological processes. Researchers can tag drugs, cancer cells, stem cells, and viruses to see where they go inside a human body. With the ability to track cells, this helps scientist understand that ways diseases work.
external image bioluminescence-05-1111-mdn.jpg
Bioluminescence can be used in the military as a safer ligtht source. Since bioluminescence has less thermal energy outputed that normal lighting, making heat-seeking weapons unable to target them. Only about 20% of the light generates thermal radiation or heat. Another uses would be as a defensive "burglar alarm." Passing ships and submarines will disturb the algae and marine organism causing them to bioluminesce. This can easily give away an enemy's position and help the Navy execute their missions.

This protein can be attached to other genes with ease via gene splicing. This allows researcher to visually track the genes as they reacted with chemicals within a cell. Also, as mentioned above, GFP can be used to create glowing pets such as fish and rats.

A brief recap of Bioluminescence

Angelique S.- In the post, you mentioned that researchers are trying to develop trees to light the streets using bioluminescence. If they succeed in turning trees into streetlights, is it possible, or is there any research on using bioluminescence as a means of light for other things, such as a house light or a car light? Also, are there any problems or downsides with the application of bioluminescence in the real world, what about side effects to attaching the protein GFP to other genes to do this type of research? Blake Miranda: This last question Angelique poses, concerning the problems and side affects of the application of bioluminescence, is one that i would like to further elaborate. During my research of Autologous bone marrow transplantation, I discovered one of the possible reactions the body has is Graft vs host disease. In GVHD, the immune system of the individual recieving the bone marrow percieves the foreign material being transplanted as a threat to the body, and immediately works to fight of this material and eliminate it from the body. It seems to me that, if bioluminescent genes were transplanted into the body of an animal, that GVHD could become a possibility as well, with the immune system considering these genes as a threat to the body of the animal, and working to get rid of it as quick as possible,
Blake M. - The use of bioluminescene in the near future seems like it very well could be a great possibility in terms of renewable, non polluting sources of light, but this possibility of such a widespread use of bioluminescence brings questions to mind. The first of these questions would be, how would you turn on or off light created by such bioluminescence? It seems like a basic question, but in regular lights used today, they are turned on and off by the use of a switch, and the resulting separation and connecting of a circuit. Could this technology be imoplemented in the use of bioluminescence, or would a completely new method have to be created?

Jason: Although bioluminescence may seem like a viable source of producing renewable, non-polluting light, and thus has the possibility to replace fluorescent and LED light bulbs, however, there are many drawbacks to the use of bioluminescence.First, bioluminescence is limited by most biological species’ inability to emit a high level of light. There are experimentations filling the cells with other fluorescent proteins that can magnify the bacteria’s light however this process is still under development. Instead, of being used in the common light bulb, bio light will probably be used wherever low light levels are needed. For example, in exit signs, night-time road marks indicator lights, etc. The second limitation is that bioluminescence produces mainly blue-green colored light, which differs from the color of the currently used lights. The third limitation is its complexity which results in the inability to fulfill simple functions and conveniences. One of these conveniences is having the ability to be turned off by the press of a button or flick of a switch. Like you said, Blake, regular lights are turned on or off through the connection or separation of a circuit (thus allowing or preventing the electrons to travel throughout the system and produce light through electrical means). However, bioluminescence is more complicated in that its light is produced by biochemical reactions. So, although bacteria with the ability to produce light can be cultivated and put into a light bulb, it would be difficult to regulate the production of light as easily as a circuit does. Bio light is produced when luciferin reacts with oxygen. This process is speeded up by the catalyst luciferase. The expression of genes related to bioluminescence is controlled by the lux operon. So in order to regulate the control of light, one would have to either control the amount of oxygen allowed to react with luciferin, introduce an inhibitor to counteract the luciferase, or inhibit the lux operon. The mechanism of the lux operon is demonstrated in the video below. Although bio light could one day create energy that is self-energizing, self-repairing and even self-reproducing, right now the widespread use of bio seems to be a work in progress.