[Comparison of the cyanogen bromide peptides of vitreous body collagen and type II collagen (author's transl)]

Studies on a distinct fraction of bovine vitreous body collagen

We were able to separate pepsin-solubilized collagen of the bovine vitreous body into three distinct fractions by differential salt precipitation with 0.5 M acetic acid containing 0.7 M, 1.2 M, and 2.0 M NaCl, respectively. The 0.7 M NaCl fraction showed an electrophoretic mobility in polyacrylamide gel identical to that of type II collagen, CNBr-derived peptides very similar to type II collagen CNBr-peptides, and a reaggregation behaviour closely related to type II collagen as observed by electron microscopy. Therefore, the fibres of the bovine vitreous body appear to contain a mixture of a collagen very similar to type II collagen precipitable in the presence of 0.7 M NaCl, at least two different collagen types that can be precipitated at 1.2 M, and 2.0 M NaCl concentrations that have not been identified previously.

An analysis of rabbit vitreous collagen

Where similar techniques are employed, the properties of collagen peptides extracted from rabbit vitreous by pepsin treatment resemble those described in published reports of bovine vitreous. Further, rabbit vitreous also contains minor components that migrate on polyacrylamide gel electrophoresis more slowly than the minor 1 alpha and 2 alpha chains of rabbit cartilage. Properties of the major vitreous components suggest a mixture of the closely-related cartilage collagen chains alpha 1(II) and 3 alpha.

Isolation of different hydroxyproline containing proteins from bovine vitreous body collagen

From pepsin-solubilized vitreous body collagen three different precipitates were collected by differential salt precipitation. These three different protein fractions contain hydroxyproline and show different patterns in polyacrylamide gel electrophoresis suggesting different collagen types.