Control of antibody-antigen interaction using anion-induced conformational change in antigen peptide |
| |
Authors: | Katakura Yoshio; Miyazaki Takahiro; Wada Hitomi; Omasa Takeshi; Kishimoto Michimasa; Goto Yuji; Suga Ken-ichi |
| |
Affiliation: | Department of Biotechnology, Graduate School of Engineering and
2 Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan |
| |
Abstract: | The binding of a monoclonal antibody to an epitope peptide wascontrolled by the conformational change of the epitope peptideinduced by anions. We synthesized peptides in which the epitopesequence DTYRYI for the monoclonal antibody AU1 is located betweenamphiphilic peptides (KKLL)n and (LLKK)n. In the absence ofan appropriate anion, the peptide was in a random coil stateand the epitope was linear. In contrast, in the presence ofan appropriate anion, the peptide exhibited an anti-parallel -helical structure and the epitope was subsequently `bent'.In the presence of 41 µM triphosphate, the associationconstant between the antibody and the peptide was decreasedby one order of magnitude in the case of n = 3 and at leastthree orders of magnitude in the case of n = 4 or 5. Oligo-DNAs,as anions, dissociated the antibodypeptide complex, whereastriphosphate did not. The DNA concentrations required for 50%dissociation of the antibodypeptide complex at pH 7.5were 4x108, 1x107 and 6x106 M for decamer,octamer and hexamer DNA, respectively. |
| |
Keywords: | |
本文献已被 Oxford 等数据库收录! |
|