Intact collagen fibrils were isolated from the dermis of Cucumariu frondosa by a new method
involving exposure to a divalent cation chelator followed by extraction in water. The fibrils have
sulfated glycosaminoglycan moieties associated with their surfaces in the middle of the gap zones.
The covalently associated constituents of the fibrils include collagen and three glycosaminoglycancontaining
molecules. Two of the glycosaminoglycan-containing molecules are proteoglycans that
are solubilized by disulfide bond reduction. The third, which is the most abundant of the three,
is not solubilized by disulfide reduction, but is solubilized by proteolysis with bacterial collagenase.
Molecular collagen was extracted from isolated fibrils by pepsin digestion followed by 1 M NaCl
extraction at pH 8. The pepsin-digested collagen was insoluble in acid until it had been separated
from the fibril-associated glycosaminoglycans. The purified collagen is an (~1 trimer. Polyclonal
antibodies to C. frondosa collagen do not cross-react with Euciakris tribuloides or rat tail tendon
collagen.