title: Structural and energetic hot-spots for the interaction between a ladder-like polycyclic ether and the anti-ciguatoxin antibody 10C9Fab.
abstract: The mechanism by which anti-ciguatoxin antibody 10C9Fab recognizes a fragment of ciguatoxin CTX3C (CTX3C-ABCDE) was investigated by mutational analysis based on structural data. 10C9Fab has an extraordinarily large and deep antigen-binding pocket at the center of its variable region. We mutated several residues located at the antigen-binding pocket to Ala, and kinetic analysis of the interactions between the mutant proteins and the antigen fragment was performed. The results indicate that some residues associated with the rigid antigen-binding pocket are structural hot-spots and that L-N94 is an energetic hot-spot for association of the antibody with the antigen fragment CTX3C-ABCDE, suggesting the importance of structural complementarity and energetic hot-spot interactions for specific recognition of polycyclic ethers.
authors.affiliation: Department of Medical Genome Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8562, Japan.
authors.forename: Mihoko
authors.initials: M
authors.lastname: Ui
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tsumuraya
authors.forename: Ikuo
authors.initials: I
authors.lastname: Fujii
authors.forename: Masayuki
authors.initials: M
authors.lastname: Inoue
authors.forename: Masahiro
authors.initials: M
authors.lastname: Hirama
authors.forename: Kouhei
authors.initials: K
authors.lastname: Tsumoto
mesh_terms: D000906:Antibodies / Q000737:chemistry* / Q000235:genetics / Q000276:immunology*; D000937:Antigen-Antibody Reactions; D002922:Ciguatoxins / Q000276:immunology*; D004988:Ethers, Cyclic / Q000737:chemistry* / Q000276:immunology*; D007140:Immunoglobulin Fab Fragments / Q000737:chemistry* / Q000235:genetics / Q000276:immunology*; D007700:Kinetics; D008958:Models, Molecular; D015394:Molecular Structure; D009154:Mutation; D011083:Polycyclic Compounds / Q000737:chemistry* / Q000276:immunology; D020349:Surface Plasmon Resonance
chemical_list: D000906:Antibodies; D004988:Ethers, Cyclic; D007140:Immunoglobulin Fab Fragments; D011083:Polycyclic Compounds; D002922:Ciguatoxins