Luciferase
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Luciferase is a generic name for enzymes commonly used in nature for bioluminescence. The name itself is derived from Lucifer, which means light-bearer. The most famous one is firefly luciferase (EC 1.13.12.7 (http://www.expasy.org/cgi-bin/nicezyme.pl?1.13.12.7)). In luminescent reactions, light is produced by the oxidation of a luciferin (a pigment), sometimes involving Adenosine triphosphate (ATP). The rates of this reaction between luciferin and oxygen are extremely slow until they are triggered by the presence of luciferase. The reaction takes place in two steps:
The reaction is very energy efficient: nearly all of the energy input into the reaction is transformed into light. As a comparison, the incandescent light bulb loses about 90% of its energy to heat.
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Luciferin and luciferase do not refer to a particular molecule. They are generic terms for a light-producing chemical and its associated regulatory compound, usually a protein. A wide variety of species regulate their light production using a luciferase. The most famous is the firefly, although it even exists in organisms as different as the Jack-O-Lantern mushroom and many marine creatures. In the firefly, the oxygen required is supplied through a tube in the abdomen called the abdominal trachea. Some organisms, notably the click beetles, have several different luciferase enzymes which each can produce different colors from the same luciferin.
Luciferase can be produced in the lab through genetic techniques, and has a wide variety of uses. Genes for luciferase can be genetically engineered into organisms so that they glow when exposed to the right luciferin. This allows visualization of certain biological processes, stages of infection, and provides other valuable sources of information. Mice, silkworms, and potatoes are just a few organisms that have already been engineered to produce the chemical. Luciferase can be used in blood banks to determine if red blood cells are starting to break down. Laboratories can use luciferase to produce light in the presence of certain diseases. The possibilities for uses for luciferase continue to expand.
See
External link
- Chemistry of Bioluminescence (http://www.lifesci.ucsb.edu/~biolum/chem/)de:Luciferase