3KPH

Crystal structure of Mycoplasma arthritidis-derived mitogen

3KPH の概要

• エントリーDOI: 10.2210/pdb3kph/pdb
• 関連するPDBエントリー: 1R5I 2ICW
• 分子名称: Superantigen, PHOSPHATE ION (3 entities in total)
• 機能のキーワード: superantigen, mam, 3d-domain swap, immune system
• 由来する生物種: Mycoplasma arthritidis
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 51426.10

構造登録者

Liu, L.H.,Li, H.M. (登録日: 2009-11-16, 公開日: 2010-05-12, 最終更新日: 2023-09-06)

主引用文献

Liu, L.,Li, Z.,Guo, Y.,Vanvranken, S.J.,Mourad, W.,Li, H.
Crystal Structure of the Mycoplasma arthritidis-Derived Mitogen in Apo Form Reveals a 3D Domain-Swapped Dimer.
J.Mol.Biol., 399:367-376, 2010

PubMed Abstract: Mycoplasma arthritidis-derived mitogen (MAM) is a superantigen that can activate large fractions of T cells bearing particular Vbeta elements of T cell receptor. Here, we report the crystal structure of a MAM mutant K201A in apo form (unliganded) at 2.8-A resolutions. We also partially refined the crystal structures of the MAM wild type and another MAM mutant L50A in apo forms at low resolutions. Unexpectedly, the structures of these apo MAM molecules display a three-dimensional domain-swapped dimer. The entire C-terminal domains of these MAM molecules are involved in the domain swapping. Functional analyses demonstrated that the K201A and L50A mutants do not show altered ability to bind to their host receptors and that they stimulate the activation of T cells as efficiently as does the wild type. Structural comparisons indicated that the "reconstituted" MAM monomer from the domain-swapped dimer displays large differences at the hinge regions from the MAM(wt) molecule in the receptor-bound form. Further comparison indicated that MAM has a flexible N-terminal loop, implying that conformational changes could occur upon receptor binding.

PubMed: 20417218
DOI: 10.1016/j.jmb.2010.04.030

実験手法

X-RAY DIFFRACTION (2.8 Å)