Collagen properties

Albeit in normal tissue, collagen is degraded primarily by collagenases, also by non-sulfated isoforms of trypsins commonly found in tumors, which cleave only the non-helical and unfolded regions of collagen chains without action over the stabilization of triple helices. This type of action is similar to sulfated trypsins produced by pancreas [10]. 

In addition to enzymatic degradation, the collagen xmdergoes degradation by hydrolysis under the influence of temperature and/or mechanical stress. The presence 

Cell interaction of collagen. Most cells do not have receptors for the synthetic polymers and thus the synthetic polymers-based products are less suitable for tissue engineering application. Thus by mixing collagen, which is an integral component of extracellular matrix, with natural or synthetic polymers improves the adhesion characteristics for products. At the same time, extracellular matrix proteins such as laminin, fibronectin and vitronectin are not absorbed on to the surface of polymeric products prepared as hydrogels, due to the hydrophilic nature of polymeric network components. 

The collagen matrix stimulates collagen production by the seeded cells in biomaterial. This property is not found for synthetic biomaterials. It owes its binding domains to integrins, which favor the attachment of cells in culture necessary for the growth, differentiation, replication and metabolic activity of the cells. 

Microfibrillar collagen is an excellent hemostat agent used in several studies in order to prepare biomaterials for pharmaceutical and medical application [19]. The hemostatic character of collagen is manifested when the platelets in contact with collagen material adhere to its surface, desorb and aggregate and activate the thrombin in fibrinogen, which ends with the appearance of thrombus. 

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Structure of Collagen Properties of Collagen Rich Tissue... 

Definition Proteinaceous extractives obtained from hides, bones, and other collagen-rich substances of animal origin hydrolysis prod, of collagen Properties Yel. to dk. amber hard solid sol. in water dens. 1.27 kg/l... 

Formula RCO-NH(CH2)3N"(CH3)2CH2CHOHCH2.X-, RCO = coconut oil fatty acid, X = peptide radical derived from hydrolyzed collagen Properties Amphoteric... 

Definition Condensation prod, of lauric acid chloride and hydrolyzed collagen Properties Alcohol-sol. 

Blends based on collagen without chemical modification with natural or synthetic polymers, or hybrid materials prepared with inorganic component in the form of nanoparticles or bulk material, can have great potential application in pharmaceutical areas due to their ability to mimic the extracellular matrix both morphologically and chemically (also see Table 13.3). Reasons for preparation of collagen-based blends are related to improvement of collagen properties, low cost of preparation method, simplification or improvement of preparation technology, etc. 

Maiorano, G., C. Cavone, R.J. McCormick, A. Ciarlariello, M. Gambacorta and A. Manchisi, 2007. The effect of dietary energy and vitamin E administration on performance and intramuscular collagen properties of lambs. Meat. Sci. 76, 182-188. 

Synonyms Collagen, lauroyl derivs. Lauroyl hydrolyzed animal protein Proteins, hydrolysates, reaction prods, with lauroyl chloride Definition Condensation prod, of lauric acid chloride and hydrolyzed collagen Properties Alcohol-sol. 

Synonyms Soluble animal collagen Soluble native collagen Definition Nonhydrolyzed, native protein derived from connective tissue of young animals consists of a mixt. of precursors of mature collagen Properties M.w. 285,000... 

Fibrous proteins can serve as structural materials for the same reason that other polymers do they are long-chain molecules. By cross-linking, interleaving and intertwining the proper combination of individual long-chain molecules, bulk properties are obtained that can serve many different functions. Fibrous proteins are usually divided in three different groups dependent on the secondary structure of the individual molecules coiled-coil a helices present in keratin and myosin, the triple helix in collagen, and P sheets in amyloid fibers and silks. 

It is well known that native collagen containes tripeptide sequences, which alone are not capable of building up a triple helix (e.g. Gly-Pro-Leu, Gly-Pro-Ser) when they exist as homopolypeptides. The synthesis of threefold covalently bridged peptide chains opens up the possibility of investigating the folding properties of such weak helix formers, because the bridging reduces the entropy loss during triple-helix formation and thereby increases the thermodynamic stability of the tertiary structure. Therefore, we have... 

The diversity in primary, secondary, tertiary, and quaternary stmctures of proteins means that few generalisations can be made concerning their chemical properties. Some fulfil stmctural roles, such as the collagens (found in bone) and keratin (found in claws and beaks), and are insoluble in all solvents. Others, such as albumins or globulins of plasma, are very soluble in water. Still others, which form part of membranes of cells, are partly hydrophilic ( water-loving , hence water-soluble) and partly lipophilic ( lipid-loving , hence fat-soluble). 

The properties described above have important consequences for the way in which these skeletal tissues are subsequently preserved, and hence their usefulness or otherwise as recorders of dietary signals. Several points from the discussion above are relevant here. It is useful to ask what are the most important mechanisms or routes for change in buried bones and teeth One could divide these processes into those with simple addition of new non-apatitic material (various minerals such as pyrites, silicates and simple carbonates) in pores and spaces (Hassan and Ortner 1977), and those related to change within the apatite crystals, usually in the form of recrystallization and crystal growth. The first kind of process has severe implications for alteration of bone and dentine, partly because they are porous materials with high surface area initially and because the approximately 20-30% by volume occupied by collagen is subsequently lost by hydrolysis and/or consumption by bacteria and the void filled by new minerals. Enamel is much denser and contains no pores or Haversian canals and there is very, little organic material to lose and replace with extraneous material. Cracks are the only interstices available for deposition of material. 

The ability of these peptidomimetic collagen-structures to adopt triple helices portends the development of highly stable biocompatible materials with collagenlike properties. For instance, it has been found that surface-immobilized (Gly-Pro-Meu)io-Gly-Pro-NH2 in its triple-helix conformation stimulated attachment and growth of epithelial cells and fibroblasts in vitro [77]. As a result, one can easily foresee future implementations of biostable collagen mimics such as these, in tissue engineering and for the fabrication of biomedical devices. 

Bray KL (2001) High Pressure Probes of Electronic Structure and Luminescence Properties of Transition Metal and Lanthanide Systems. 213 1-94 Brinckmann J (2005) Collagens at a Glance. 247 1-6 Bronstein LM (2003) Nanoparticles Made in Mesoporous Solids. 226 55-89 Bronstrup M (2003) High Throughput Mass Spectrometry for Compound Characterization in Drug Discovery. 225 275-294... 

Collagen, because of its unique structural properties, has been fabricated into a wide variety of forms including crosslinked films, meshes, fibers, and sponges. Solid ocular inserts have also been prepared from purified animal tissues. 

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