The Chemistry of Bioluminescence

Introduction

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Bioluminescence is the production and emission of light within a living organism. Many different organisms can bioluminesce, including fireflies, deep sea fish, plankton, bacteria, and some crustaceans. It is used for camouflage, protection, recognition between members of the same species, and to light the way in the deep sea. I chose this topic because it has always been interesting to me, and I was curious to see how it happens. An understanding of bioluminescence has interesting applications, as well. Some researchers are able to use it to track clumps of cancer cells and monitor how the cancer cells changeover time, among other things.

Composition of ...

Luciferin: synthetic luciferin has the chemical formula C11H8N2O3S2, but there are many different types depending on the organism.
Luciferase
Oxygen

Cofactors: Most of the time, when luciferin reacts with luciferase and is oxidized, there is at least one cofactor. Many things can be cofactors, like adenosine triphosphate (ATP) (C10H16N5O13P3), or ionic magnesium

Main Chemicals, Compounds, Components

Luciferin: this is the molecule that produces the light when another molecule (or group of molecules) excites it. Each bioluminescent organism has a unique luciferin and they vary in chemical structure. It can be man made, and this synthetic luciferin has a chemical structure of C11H8N2O3S2.

Luciferase: this is the enzyme that catalyzes the reaction with luciferin. Each luciferin has a specific and unique luciferase. Luciferase is used in bioluminescent imaging as an imaging reporter. It tracks cells, infections, gene expression, and cellular response to treatment

Chemistry's Role

Bioluminescence is chemiluminescence that occurs in a living organism. In chemiluminescence, a molecule gets excited by an outside energy source, and goes to a higher energy state than its usual ground state. When the molecule loses energy, it returns to its ground energy state, and emits a photon of light. In bioluminescence, the molecule that gets excited by an outside source is luciferin, and the outside source is the catalyst luciferase, and though all reactions contain molecular oxygen, it has different functions depending on the organism. The reaction also often involves another cofactor. Bioluminescent organisms are able to glow for a long period of time because the molecules involved in the reaction are rapidly losing and gaining energy, and so they are releasing many photons. Different colors are produced depending on the wavelength of the light, usually within the visible light spectrum. For example, in one specie of firefly, firefly luciferin, luciferase, ATP, and ionic magnesium combine to form a complex, which then gets oxidized, exciting the molecule and causing the emission of light. Fireflies typically bioluminesce in yellowish colors, which are produced by a wavelength of around 600 to 650 nanometers. However, bioluminescence in bacteria is a little different. Bacteria-specific luciferin (FMNH2) is oxidized and combines with long-chain aldehyde and is then catalyzed with luciferase.

Background Research

Bioluminescence is the light emitted by an organism, it can be internally synthesized or come from an outside source. It can be found in bacteria, animals in the deep sea, fireflies and more. It is not known to exist in any plants, amphibians, or mammals, unless unnaturally. Chemiluminescence is the chemical reaction that results in bioluminescence, and this reaction gives off almost no heat. Adenosine Triphosphate (ATP) is a high energy molecule that provides energy for mechanisms in organisms that need it.

Resources

http://biolum.eemb.ucsb.edu/chem/

Created from at least luciferin (molecule that produces light) and luciferase (catalyst)

Involves oxidation of luciferin

Light is supplied by a chemical reaction

http://www.britannica.com/science/bioluminescence

The purposes of bioluminescence

Bioluminescent organisms

Reaction gives off little heat

http://pdb101.rcsb.org/motm/78

Luciferase can help track groups of cells like cancer cells

http://education.nationalgeographic.org/encyclopedia/bioluminescence/

Most marine bioluminescence is in the blue-green part of the visible light spectrum, which are easily visible in the deep ocean