Collagen weight

Table 2. Survey of synthesized collagen models. Average molecular weights (M)... 

Gel filtration on Sephadex G 25, G 50 or G 75 beads was just available. After standardization with peptides and proteins of known length, the molecular weight of the respective fraction could be determined. Also cyanogen bromide peptides of collagen chains were available in the later sixties, thus leading to a more consistent standardization15"17. ... 

Figure 9.3. Percentage of non-detectable amino acids in collagen extracts from archaeological human skeletons. Numbers on top of the columns indicate number of carbon atoms per amino acid. XW = weighted mean of % loss (cf. text). Only high-carbon amino acids are more frequently lost than the average.

Paleodiet studies have focused on the analysis of collagen, due to its ability to survive in ancient bone. Like all proteins, collagen is composed of amino acid (AA) units present in relatively constant proportions characteristic of the specific protein. The isotopic composition of a sample of collagen is the weighted average of the 5 C values of each of the constituent amino acids. 

Continuous curve.- f(F) = F (The weighting fimction implying total routing collagen carbon derives only from diet protein). 

There are approximately 200 other proteins present in bone, though most of them are present only in trace amounts (Delmas et al., 1984 Linde et al., 1980, as cited in van Klinken, 1991). The second most common bone protein, osteocalcin, comprises 1-2 weight % of total fresh bone. Osteocalcin bonds with both the bone mineral fraction and bone collagen, but it seems to be unstable in solutions. Due to its small molecular size and strong mineral stabilization, osteocalcin can survive up to 50.000 years (C.l. Smith et al., 2005), and it may offer an alternative to the use of collagen in paleoenvironmental stable isotope research. However, osteocalcin s role and importance in this field of study has yet to be defined (Collins et al., 2002). 

Repetitive overuse of a tendon can cause cellular changes in the tissues. Specifically, collagenous tendon tissue is replaced with tissue that lacks the longitudinal structure of a normal tendon.16 As a result, the tendon progressively loses elasticity and its ability to handle stress or weight. This makes the tendon vulnerable to rupture or inflammation (tendonitis and tenosynovitis). 

Vierboom MP, Zavodny PJ, Chou CC, et al. Inhibition of the development of collagen-induced arthritis in rhesus monkeys by a small molecular weight antagonist of CCR5. Arthritis Rheum 2005 52(2) 627-636. 

The bones and teeth of humans and other vertebrate animals, for example, consist mainly of a composite material made up of an organic substance, collagen, and a biomineral, calcium carbonate phosphate (see Textboxes 32 and 61). The latter, which makes up about two-thirds of the total dry weight of bone, is composed of calcium phosphate containing between 4-6% calcite (composed of calcium carbonate) as well as small amounts of sodium, magnesium, fluorine, and other trace elements. The formula Ca HPChXPChMCChXOH) approximately represents its composition its crystal structure is akin to that... 

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