title: Helical structure of human native collagen.
abstract: A "fibroleiomyoma" of the lung obtained from a 40-year-old man as a surgical specimen was studied with both the light and the electron microscope. The unusual collagen in this tumor displayed a filamentous helical structure. The filaments measured 50 Angstroms across. Most of the fibrils did not show periodicity. Some, however, showed periodicity of about 700 A. Those with periodicity were smaller in diameter than the fibrils without periodicity. These observations suggest a helical structure of native collagen and may also represent weak cross-linking of tropocollagen in this tumor. This is the first report of collagen showing a helical filamentous structure from human material.
mesh_terms: D000328:Adult; D055598:Chemical Phenomena; D002621:Chemistry; D003094:Collagen / Q000032:analysis*; D005350:Fibroma / Q000473:pathology*; D006651:Histocytochemistry; D006801:Humans; D007889:Leiomyoma / Q000473:pathology*; D008175:Lung Neoplasms / Q000473:pathology*; D008297:Male; D014332:Tropocollagen / Q000032:analysis
chemical_list: D014332:Tropocollagen; D003094:Collagen