Fibril, collagen

Beaded filament and anchoring fibril collagens (types VI and VII) 508... 

Triple helical collagen molecule Collagen fibril Collagen fiber Primary fiber bundle (subfascicle) Secondary fiber bundle (fascicle) Tertiary fiber bundle (fasdde)... 

Fibrous proteins are long-chain polymers that are used as structural materials. Most contain specific repetitive amino acid sequences and fall into one of three groups coiled-coil a helices as in keratin and myosin triple helices as in collagen and p sheets as in silk and amyloid fibrils. 

Collagen types I, II, and III form strong, organized fibrils, consisting of staggered arrays of tropocollagen molecules (Figure 6.19). The periodic... 

Scurvy results from a dietary vitamin C deficiency and involves the inability to form collagen fibrils properly. This is the result of reduced activity of prolyl hydroxylase, which is vitamin C-dependent, as previously noted. Scurvy leads to lesions in the skin and blood vessels, and, in its advanced stages, it can lead to grotesque disfiguration and eventual death. Although rare in the modern world, it was a disease well known to sea-faring explorers in earlier times who did not appreciate the importance of fresh fruits and vegetables in the diet. 

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 ). 

Grenz zone prominent, elastogenesis, elastosis, collagen degeneration, loss of anchoring fibrils... 

The 19 types of collagen mentioned above can be subdivided into a niimbet of classes based primarily on the sttucmtes they fotm (Table 48-2). In this chaptet, we shall be primarily concerned with the fibril-forming collagens I and II, the majot collagens of skin and bone and of cattilage, tespectively. However, mention will be made of some of the othet collagens. 

COLLAGEN TYPE I IS COMPOSED OF A TRIPLE HELIX STRUCTURE FORMS FIBRILS... 

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