title: Gamma-crosslinked collagen gel without fibrils: analysis of structure and heat stability.
abstract: This paper reports an analysis of the structure and heat stability of two different collagen gels: conventional collagen gel (neutral gel) and gel without collagen fibrils (acidic gel), previously reported. We performed differential scanning calorimetry (DSC), observations by scanning electron microscope (SEM), observations by atomic force microscope (AFM), and small angle X-ray scattering (SAXS). Collagen fibrils were clearly observed in the neutral gel but not in the acidic gel by both SEM and AFM. A clear endothermic peak was observed at 53-55 degrees Celsius, representing disassembly of collagens in collagen fibrils in the neutral gel but not in the acidic gel. Only a small broad endothermic peak, at 35-43 degrees Celsius, representing the deformation of the triple helical structure of collagen, was observed in the acidic gel. The SAXS pattern also suggested that the neutral gel had a more heterogeneous structure than the acidic gel. The experimental results described here are compatible with the model proposed in a previous paper, and indicate more clearly that the acidic gel has no collagen fibrils and has a different molecular assembly state of Type I collagen than the neutral gel.
authors.affiliation: Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-2 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8570, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Koshimizu
authors.forename: Masahiko
authors.initials: M
authors.lastname: Bessho
authors.forename: Shiho
authors.initials: S
authors.lastname: Suzuki
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Yuguchi
authors.forename: Shinichi
authors.initials: S
authors.lastname: Kitamura
authors.forename: Masayuki
authors.initials: M
authors.lastname: Hara
mesh_terms: D002152:Calorimetry, Differential Scanning; D003094:Collagen / Q000737:chemistry*; D006358:Hot Temperature; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D011487:Protein Conformation; D012542:Scattering, Radiation
chemical_list: D003094:Collagen