title: Structural study of hNck2 SH3 domain protein in solution by circular dichroism and X-ray solution scattering.
abstract: We have done conformational study of hNck2 SH3 domain by means of far-ultraviolet (far-UV) circular dichroism (CD) and X-ray solution scattering (XSS). The results indicated that the following: (1) hNck2 SH3 domain protein exhibited concentration dependent monomer-dimer transition at neutral pH, while the secondary structure of this protein was independent of the protein concentration. (2) The hNck2 SH3 domain also exhibited pH dependent monomer-dimer transition. This monomer-dimer transition was accompanied with helix-β transition of the secondary structural change. Moreover, the acid-induced conformation, which was previously studied by Liu and Song by CD and nuclear magnetic resonance (NMR), was found to be not compact, but the conformation of the protein at acidic pH was similar to the cold denatured state (C-state) reported by Yamada et al. for equine β-lactoglobulin. We calculated that a structure of the equilibrium helix-rich intermediate of the hNck2 SH3 domain by DAMMIF program.
authors.affiliation: Department of Physics, Kansai Medical University, 18-89 Uyama-Higashi, Hirakata 573-1136, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Matsumura
authors.forename: Masaji
authors.initials: M
authors.lastname: Shinjo
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Matsui
authors.forename: Kaoru
authors.initials: K
authors.lastname: Ichimura
authors.forename: Jianxing
authors.initials: J
authors.lastname: Song
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kihara
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry* / Q000378:metabolism; D002942:Circular Dichroism; D019281:Dimerization; D006801:Humans; D006863:Hydrogen-Ion Concentration; D015513:Oncogene Proteins / Q000737:chemistry* / Q000378:metabolism; D017433:Protein Structure, Secondary; D053838:Scattering, Small Angle; D014961:X-Ray Diffraction; D018909:src Homology Domains
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C485544:NCK2 protein, human; D015513:Oncogene Proteins