Collagens fibrillar

Fish collagen fibrillar gels have not been studied, with the exception of shark collagen (Nomura et al., 2000a,b), probably due to their low denaturation temperature (Tt]), which renders these materials difficult to handle. The Tt] of shark collagen solution is approximately 30°C (Nomura et al., 1995), which results in the dissolution of the fibrillar gel of this collagen at 37°C (Nomura et al., 2000a). This indicates that the gel could not be practically used at the actual physical temperature of human medical application. The Tt] of chum salmon is approximately 19 °C (Kimura et al., 1988 Matsui et al., 1991), which is the main reason to be unstable at the actual physical temperature of human body. As the... 

Up to this point, all collagen fibrillar structures discussed are of the 65 to 67 nm axial repeat type, the most prevalent collagen form in animals. However, additional forms have been observed in vivo, or in pathological... 

Although there is a strong molecular and nanoscopic driving force behind our understanding of the functionality of collagen fibrillar structures, the mesoscopic and macroscopic properties of the tissue are where the structural integrity manifests itself. One of the differences in mechanical resistive properties between tissues such as skin and tendon is the feltwork nature of fibril distribution in skin. This allows resistance to strain to occur within a two-dimensional plane. In contrast, tendon is required (normally) to resist strain only along its axis. 

Similar arguments relative to the importance of hydrogen bonding in collagen fibrillar structure are also derived from a comparison of the shrinkage temperatures and compositions of mammalian and fish skin collagens. The latter, which possesses (see Section II, 5) fewer hydrox-ylic side chains than does the former, also has less hydrothermal stability (92). 

Wess, T. J. (2008). Collagen Fibrillar Structure and Hierarchies. In Collagen Structure and Mechanics. P. Eratzl (Ed.), Springer... 

Prior, J., Wallace, D., Hamer, A. and Powers, N., A sprayable hemostat containing fibrillar collagen, bovine thrombin, and autologous plasma. Ann. Thome. Surg., 68, 479-485 (1999). 

Activation of matrix metalloproteinases (MMP) is also involved in vascular and cardiac remodelling. For example, the fibrillar collagen matrix of the heart... 

Model peptides that could build up quarternary fibrillar structures are not yet known. Though complete explanation of the interdependence between the primary structure and the stability of the quarternary structure has not yet been possible, i.e. the role of the different amino acids in collagen could be understood completely only in correlation with the fibril formation (formation of polar and hydrophobic clusters ). 

Table 48-3. Order and location of processing of the fibrillar collagen precursor.

D.A. Slatter, N.C. Avery, A J. Bailey, Collagen in its Fibrillar State is Protected from Glycation, The International Journal of Biochemistry Cell Biology, 40(10), 2253 2263 (2008). 

MMP-1 Collagenase I (interstitial) Fibrillar collagen (prefers type III)... 

MMP-8 Neutrophil collagenase Fibrillar collagen (prefers type I), aggrecan... 

Fibrillar forms of biological macromolecules—such as collagen, DNA, muscle proteins, and filamentous viruses—have been elucidated using fiber and powder diffraction methods (Fraser and MacRae, 1973). 

R. U. Agu, M. Jorissen, T. Willems, P. Augustijns, R. Kinget, and N. Verbeke. In-vitro nasal drug delivery studies Comparison of derivatised, fibrillar and polymerised collagen matrix-based human nasal primary culture systems for nasal drug delivery studies. J Pharm Pharmacol 53 1447-1456 (2001). 

---