JamesMaoJeansEnzyme

=Laccase: the Jeans Enzyme=


 * Laccase** is an enzyme that usually reacts on **phenolic substrates** (although it actually can react with a wide range of substrates). Phenolic substrates are substances that contain the corrosive, poisonous, acidic compound **C****6****H****5****OH**. [[image:whiterotfungi.jpg width="184" height="121" align="right"]]

Laccase refers to a family of enzymes, all of which are **multi-copper oxidases**. This means that laccases are able to cause oxidations (they especially have the ability to react with oxygen molecules).

A major use of laccase is in the **textile industry**. When laccase is used on denim fabric, it attacks the indigo color of the jeans and leaves only the white. The process is too complex (delignification?! feroylated carbohydrates?!) for mere SL students not even halfway through Year I to understand, but essentially, it takes three chemicals in order for this reaction to work: the laccase, the substrate in the jeans, and a mediator chemical. The laccase acts through the mediator chemical and the ensuing oxidation **bleaches the fabric**. Since jeans are made of an outer layer of indigo color and an inner yellowish-white fabric, the laccase reveals the white color and helps give **frayed** jeans their worn look.

Laccase is used for other purposes besides bleaching jeans. It has been used for pulp and **paper** (to make the paper we use white) and **food processing**. Bread volume has been found to increase when laccase is introduced to the wheat product. In the experimental stage are attempts to use laccase for detoxification of certain chemicals.

Laccase can be found in plant and fungi (such as the white-rot bracket fungus shown above), though recently it was discovered in bacteria. The first case of isolated laccase was in 1883, where it was found in a Japanese lacquer tree.

For a complete understanding of exactly how laccase reacts with the substances in denim jeans to cause bleaching, [|this site] details the many different reactions. The language is far beyond the layman's grasp, so peruse at your own peril.

//this page by James Mao (IB Biology SL Block F)//

Sources:
http://www.enzymeindia.com/enzymes/denim-enzymes.asp http://www.chem.ox.ac.uk/icl/faagroup/laccase.html http://content.febsjournal.org/cgi/content/full/272/14/3640 http://men.style.com/slideshows/mens/standalone/gq/fashion/0506/Jeans/00002v.jpg