Heterogeneity of collagen isolated from the Guérin epithelioma.

Molecular polymorphism of collagen isolated from the Guérin epithelioma was investigated. Tumour homogenate was digested with pepsin in acidic solution. Above 70% of total tumour collagen was solubilized by this procedure and then it was submitted to fractionation by stepwise increase of NaCl concentration. It was found that collagen of this tumour is not a homogeneous protein. At least two different collagen types were found. As can be concluded from the chromatographic analyses, electrophoretic properties and amino acid composition, the tumour contains type I and type III collagen.