title: [Dynamic atomic force microscopic observation of the three-dimensional conformation of protein A-gold single molecule].
abstract: OBJECTIVE
  To determine the three-dimensional (3D) conformation of staphylococcal protein A-gold (SPA-G) single molecule using atomic force microscope (AFM) so as to evaluate the feasibility of using this molecule for in situ labeling of the neuronal membrane protein.
  
  
  METHODS
  AFM was used to acquire the images of SPA-G binding to the surface of mica under physiological condition for determining the 3D conformation of the molecule.
  
  
  RESULTS
  SPA-G single molecule was shown to contain a characteristic structure with a chain in the shape of mirror image of the letter C, which had the dimension of 48.80 nm x 42.13 nm x 20.53 nm.
  
  
  CONCLUSIONS
  AFM provide a new means for morphological investigation of the biomacromolecule at the nanometer scale in physiological conditions, and SPA-G can be utilized for in situ labeling of the neuronal membrane receptors.
authors.affiliation: Department of Neurosurgery, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China. yu-yg@tom.com
authors.forename: Yi-Gang
authors.initials: YG
authors.lastname: Yu
authors.forename: Ru-Xiang
authors.initials: RX
authors.lastname: Xu
authors.forename: Ying-Qian
authors.initials: YQ
authors.lastname: Cai
authors.forename: Xiao-Dan
authors.initials: XD
authors.lastname: Jiang
authors.forename: Yi-Quan
authors.initials: YQ
authors.lastname: Ke
mesh_terms: D017979:Gold Colloid / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D008958:Models, Molecular; D008968:Molecular Conformation; D016194:Receptors, N-Methyl-D-Aspartate / Q000737:chemistry; D013205:Staphylococcal Protein A / Q000737:chemistry*
chemical_list: D017979:Gold Colloid; D016194:Receptors, N-Methyl-D-Aspartate; D013205:Staphylococcal Protein A