Collagen
By Grace Martini and Katja Kleine

external image Collagen2.jpg
Basic Information
Collagen can be both a natural polymer and a synthetic polymer. Natural collagen is found in human and animal skin. Natural collagen is the most abundant protein in the human body. Synthetic collagen is an elastomer, meaning that it is a polymer that has the property of elasticity. As a synthetic polymer, it is in the form of short triple helices, held together and lengthened by a sticky end. The synthetic form of Collagen is biodegradable. Collagen is both the common and technical name.

Monomers
All polymers are made up of different monomers. The collagen monomers are:
- Glycine
- Proline
- Hydroxyproline
- Hydroxylysine. Depending on the type of collagen it can sometimes have
disaccharide (a sugar)

These are combined in this formation
- Gly-Pro-Y (Glycine-Proline,Tryptophan)
- Gly-X-Hydoxyproline (Glycine- Cysteine-Hydroxyproline)
- Gly-Pro-Hyp (Glycine-Proline-Hydroxyproline)

Note: the X and Y can be replaced with any of the 20 amino acids. In this case Y has been reaplced with Tryptophan, and X has been replaced with Cysteine

external image collagen_(alpha_chain).jpg

Video of how to build a Collagen polymer:
2008-05-15_0930.swf

Physical Characteristics

The collagen polymer is shaped in a Madras helix (triple helical structure). The structure of collagen has three monomers. These three amino acid monomers are tightly bonded which makes them appears as one single monomer. Collagen’s main physical characteristic is elasticity. Collagen has multiple hydrogen bonds, which when pressure is applied the bonds can be broken. When the pressure is released the bonds are recreated. This gives the illusion that the molecule is being stretched.


Chemical Characteristics

Cross linkages dose occur in the Collagen polymer. Because the Oxygen side of the molecule is so electronegative, the three helices are strongly bonded together. There are three separate monomers, but by looking at the molecule they are so strongly attracted to each other, it looks like one monomer. The significance of cross linking means that you have a molecule which a greater length, thus is has a greater strength.

Natural uses
Collagen is the main protein of connective tissues in animals and the most abundant protein in mammals. Collagen is the main component of fascia, cartilage, ligaments, tendons, bone and teeth. Collagen is responsible for skin strength and elasticity, the degradation leads to wrinkles and aging.

Industrial uses
Collagen has become a key factor in many surgical procedures. Most medical forms of collagen are derived from young cattle. It is taken from young cattle, because the triple helices are not fully cross linked. It is also used to bring temporary elasticity back to your skin with collagen injections. These lessen the appearance of wrinkles. It can also be used to plump lips. As people get older, their bodies stop producing collagen. When this reaction happens, the skin uses it elasticity which causes the skin to become wrinkly. This is the reason may people get collagen injections as they get older. Since, the body stops producing collagen, which is biodegradable, synthetic is used to replace it. In surgical procedures synthetic collagen acts with the same elasticity as natural collagen found in skin, which allows it to function effectively for medical reasons.

external image lips.jpg


Interesting Facts about Collagen
1. Brittle bone disease has much to do with low levels of collagen
2. 75% of skin is collagen
3. Comes from the Greek root meaning "glue producing"


Works Cited
BIOSPECIFICS TECHNOLOGIES CORP. Collagense & Collagen What is Collagen? 14 May 2008 <http://www.biospecifics.com/collagendefined.html>.
Elsevier. Scirus for scientific information only. 2008. 14 May 2008 <http://www.scirus.com/srsapp/search?q=Collagen&t=all&sort=0&g=s>.
Fibrogen. Fibrogen. 2008. 14 May 2008 <http://www.fibrogen.com/>.
Harrison, Karl. Chemistry, Structures & 3D Molecules @ 3Dchem.com. 2005. 14 May 2008 <http://www.3dchem.com/molecules.asp?ID=195>.
Reciprocal Net site . Reciprocal Net. 2002-2008. 14 May 2008 <http://www.reciprocalnet.org/recipnet/showsamplebasic.jsp?sampleId=27344779>.
Royal Society of Chemistry. RSC Advancing the Chemical Sciences. 2008. 14 May 2008 <http://www.rsc.org/chemistryworld/News/2006/February/14020602.asp>.
Science A GoGo. Science A GoGo . 14 February 2006. 14 May 2008. <http://www.scienceagogo.com/news/20060114021501data_trunc_sys.shtml>.

Wikipedia, the free encyclopedia. Wikipedia. 15 May 2008 <Wikipedia.org>.
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