title: Skin collagen has an unusual d-spacing.
abstract: Small angle X-ray diffraction patterns show a d-spacing of 65 +/- 0.5 nm for the collagen in wet intact skin of amphibian larvae (tadpole) as well as from that of nature frogs, chickens and mice. The collagen in these tissues is largely collagen I which exhibits a d-spacing of 67 +/- 0.5 nm in wet intact unstretched tendons. The d-spacing of the skin collagen did not decrease on drying, while it is well known that that of tendon collagen does decrease on drying. The reasons for the decreased d-spacing in the normal skin are not known but we suggest that the different glycosaminoglycan content of skin may be an important factor.
mesh_terms: D000818:Animals; D001001:Anura; D055598:Chemical Phenomena; D002621:Chemistry; D002645:Chickens; D003094:Collagen / Q000032:analysis*; D006025:Glycosaminoglycans / Q000378:metabolism; D007814:Larva; D051379:Mice; D011894:Rana pipiens; D012867:Skin / Q000032:analysis*; D013710:Tendons / Q000032:analysis; D014867:Water; D014961:X-Ray Diffraction
chemical_list: D006025:Glycosaminoglycans; D014867:Water; D003094:Collagen