中文摘要：

膜融合是有包膜病毒入侵靶细胞的关键步骤,低pH、受体结合、二者兼具或其他尚未界定的机制均可触发病毒融合蛋白的构象重排,介导病毒包膜与靶细胞膜或内体膜间的融合。组氨酸（histidine,His）残基是唯一一个质子化状态变化（pKa~6~7）接近于病毒融合阈值（~pH6）的氨基酸,参与多种低pH依赖的病毒融合蛋白构象转变及膜融合,对其可能作用机制的阐述将有助于抗病毒药物的研制与发展。

英文摘要：

Member fusion is a critical step of enveloped viruses to enter target cells. The fusion of viral en- velope with target cell membrane or endosomal membrane is mediated by viral fusion protein, whose confor- mational rearrangements can be triggered by low pH, receptor binding, both or other undefined mechanisms. Histidine （His） residue is believed to be involved in low pH- dependent conformational transitions of viral fusion proteins and subsequent member fusion since it is the only residue whose protonation state changes （pKa-6-7） is close to the fusion threshold of viruses at -pH6. The illustration of the possible mechanisms will contribute to the design and development of anti-viral drugs.