Collagen, amino acid composition

The fifteen samples analyzed for amino acid composition were compared to a human type 1 collagen standard. There are no significant differences in amino acid composition among these samples, which range in age from stillbirth to adult. Analytical error is 10%. All samples show the typical composition of type 1 collagen (Table 1.1). Based on these results there is no reason to suspect differential preservation of specific amino acids in the small bones of infants in comparison to bones of adults and older children. 

Collagen is the quantitatively most important protein in mammals, making up about 25% of the total protein. There are many different types of collagen, particularly in connective tissue. Collagen has an unusual amino acid composition. Approximately one-third of the amino acids are glycine (Gly), about 10% proline (Pro), and 10% hydroxyproline (Hyp). The... 

Piez, K. A., Eigner, E. A., Lewis, M. S. The chromatographic separation and amino acid composition of the subunits of several collagens. Biochemistry 2, 58 (1963)... 

Eastoe, J. E., Martens, P., Thomas, N. R. The amino acid composition of human hard tissue collagens in osteogenesis imperfecta and dentinogenesis imperfecta. Calc. Tiss. Res. 12, 91 (1973)... 

Primary cell-walls of dicots contain between 5 and 10% of protein that is rich (20%) in hydroxy-L-proline.4,55,228 The wall protein also contains a relatively high content of L-alanine, L-serine, and L-threonine, and this feature is found in such animal structural-proteins as collagen.228 This characteristic, amino acid composition, together with the fact that it is difficult to extract much of the protein from cell walls under nondegra-dative conditions,229 suggests that it has a structural role in the wall.228-230... 

Within the extracellular space two procollagen peptidases act to cleave a 35-kDa peptide from the C terminus631 and a 20-kDa peptide from the N-terminal end of each of the three chains of the secreted procollagen. The amino acid composition of the peptides removed is quite unlike that of the remaining collagen monomer (also called tropocollagen) which contains one-third glycine and much proline. 

Collagen has a most unusual amino acid composition in which glycine, proline, and hydroxyproline are the dominant amino acids. Further characterization of the polypeptide chains shows that these amino acids are arranged in a repetitious tripeptide sequence, Gly-X-Y, in which X is frequently a proline and Y is frequently a hydroxyproline. This unusual amino acid sequence and the unique diffraction pat-... 

The unique Hyp residue may be important both at the molecular and higher-order structure levels in collagen. Bacteria and viruses lack prolyl hydroxylase and have no hydroxyproline in their collagen-like domains. The significant differences in their amino acid composition and sequence compared to animal collagens suggest the use of alternative stabilization strategies for the triple helix (Rasmussen et al., 2003). 

Antisilicosis effect related to amino acid composition of lung collagen 472... 

Composition and The amino acid composition of collagen is quite distinctive. Nearly one-third of post-translational its residues are Gly, while another one-quarter are Pro, significantly higher modifications proportions than are found in other proteins. The hydroxylated amino acids... 

Table 6.1. Amino acid composition of soluble collagen of Cysticercus cellulosae. (Data from Torre-Bianco, 1982J...

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