title: [Quaternion-based Characterization of Protein α Helix].
abstract: This paper proposes a method based on quaternion for characterization a helix of proteins. The method defines the parameter called Quaternion Helix Axis Spherical Distance (QHASD) on the basis of mapping protein Cα frames' helical axis onto a unit sphere, and uses QHASD to characterize the a helix of the protein secondary structure. Application of this method has been verified based on the PDBselect database, with an a helix characterization accuracy of 91.7%. This method possesses significant advantages of high detection accuracy, low computation and clear geometric significance.
authors.forename: Yonghong
authors.initials: Y
authors.lastname: Xu
authors.forename: Zefei
authors.initials: Z
authors.lastname: Chu
mesh_terms: D000465:Algorithms; D030562:Databases, Protein; D008958:Models, Molecular; D017433:Protein Structure, Secondary; D011506:Proteins / Q000737:chemistry*
chemical_list: D011506:Proteins