An autotransporter of Bordetella pertussis , virulence‐associated gene 8 (Vag8), binds and inactivates the complement regulator, C1 inhibitor (C1‐Inh), and plays a role in evasion of the complement system. However, the molecular interaction between Vag8 and C1‐Inh remains unclear. Here, we localized the minimum region of Vag8 required for interaction with C1‐Inh by examining the differently truncated Vag8 derivatives for the ability to bind and inactivate C1‐Inh. The truncated Vag8 containing amino‐acid residues 102–548, but not 102–479 and 202–648, showed the full activity of intact Vag8, suggesting that the separate 102–202 and 548–648 amino‐acid regions of Vag8 mediate the interaction with C1‐Inh.

中文翻译：

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确定与C1抑制剂相互作用所需的百日咳博德特氏菌Vag8的最小区域。

百日咳博德特氏菌的自转运蛋白，毒力相关基因8（Vag8），结合并失活补体调节剂C1抑制剂（C1-Inh），并在逃避补体系统中发挥作用。但是，Vag8和C1-Inh之间的分子相互作用仍然不清楚。在这里，我们通过检查截短不同的Vag8衍生物结合和灭活C1-Inh的能力，确定了与C1-Inh相互作用所需的Vag8的最小区域。截短的包含氨基酸残基102–548而不是102–479和202–648的Vag8显示完整的Vag8的全部活性，表明Vag8的单独102–202和548–648氨基酸区域介导了相互作用与C1-Inh。