6A77

Crystal structure of the fifth immunoglobulin domain (Ig5) of human Robo1 in complex with the Fab fragment of murine monoclonal antibody B5209B

6A77 の概要

• エントリーDOI: 10.2210/pdb6a77/pdb
• 分子名称: Roundabout homolog 1, Light chain of the anti-human Robo1 antibody B5209B Fab, Heavy chain of the anti-human Robo1 antibody B5209B Fab, ... (4 entities in total)
• 機能のキーワード: hepatocellular carcinoma antigen, angiogenesis, immune system, antibody drug
• 由来する生物種: Homo sapiens (Human); 詳細
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 56373.83

構造登録者

Mizohata, E.,Nakayama, T.,Kado, Y.,Inoue, T. (登録日: 2018-07-02, 公開日: 2019-01-30, 最終更新日: 2024-11-20)

主引用文献

Yamashita, T.,Mizohata, E.,Nagatoishi, S.,Watanabe, T.,Nakakido, M.,Iwanari, H.,Mochizuki, Y.,Nakayama, T.,Kado, Y.,Yokota, Y.,Matsumura, H.,Kawamura, T.,Kodama, T.,Hamakubo, T.,Inoue, T.,Fujitani, H.,Tsumoto, K.
Affinity Improvement of a Cancer-Targeted Antibody through Alanine-Induced Adjustment of Antigen-Antibody Interface.
Structure, 27:519-, 2019

PubMed Abstract: To investigate favorable single amino acid substitutions that improve antigen-antibody interactions, alanine (Ala) mutagenesis scanning of the interfacial residues of a cancer-targeted antibody, B5209B, was performed based on X-ray crystallography analysis. Two substitutions were shown to significantly enhance the binding affinity for the antigen, by up to 30-fold. One substitution improved the affinity by a gain of binding enthalpy, whereas the other substitution improved the affinity by a gain of binding entropy. Molecular dynamics simulations showed that the enthalpic improvement could be attributed to the stabilization of distant salt bridges located at the periphery of the antigen-antibody interface. The entropic improvement was due to the release of water molecules that were stably trapped in the antigen-antibody interface of the wild-type antibody. Importantly, these effects of the Ala substitutions were caused by subtle adjustments of the binding interface. These results will be helpful to design high-affinity antibodies with avoiding entropy-enthalpy compensation.

PubMed: 30595454
DOI: 10.1016/j.str.2018.11.002

実験手法

X-RAY DIFFRACTION (2 Å)