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溴化氰可裂解北京鸭ａｐｏＡ－Ｉ为１１个肽段，通过测定纯化后各片段分子量和Ｎ末端氨基酸序列确定片段３～１０在ａｐｏＡ－Ｉ分子中的位置，分别为６４～２４０，７４～２４０，６４～２０６，１～１３６，１～６３，１７１～２０６，２０７～２４０和１３７～１７０．并对上述片段功能进行研究，结果为：（１）这些片段均可与脂质结合形成大小不同的脂质体，其大小与片段长短成正比。（２）ＡｐｏＡ－Ｉ溴化氰片段３～１０激活ＬＣＡＴ活性分别为完整ａｐｏＡ－Ｉ的６５％、５２％、６０％、３９％、８％、７％、０％和２％，说明激活ＬＣＡＴ的活性主要存在于６４～１３６之间。（３）只有片段３、４和９形成的脂质体可与肝ＨＤＬ受体结合，其他均无明显结合力，显示氨基酸２０７～２４０是ａｐｏＡ－Ｉ与ＨＤＬ受体结合片段。
Bromide cyanogen can cleave Peking duck apoA-I to 11 peptides. The molecular weight and N-terminal amino acid sequence of each fragment were determined to determine the position of fragments 3 to 10 in apoA-I molecules, respectively, 64 ~ 240,74 ~ 240, 64 to 206, 1 to 136, 1 to 63, 171 to 206, 207 to 240, and 137 to 170. And the function of the above fragments were studied, the results are: (1) These fragments can be combined with lipids to form liposomes of different sizes, the size of the fragment is proportional to the length. (2) The 3 to 10 activated LCAT activities of ApoA-I cyanogen bromide were 65%, 52%, 60%, 39%, 8%, 7%, 0% and 2% of intact apoA-I, The activity mainly exists between 64 ~ 136. (3) Only the liposomes formed by fragments 3, 4 and 9 could bind to the HDL receptor of liver, and the other showed no obvious binding force, indicating that amino acids 207-240 were apoA-I and HDL receptor binding fragments.