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我们以前的实验证明ＨＩＶ－１ｇｐ４１Ｎ端２３肽即融合肽ＨＩＶｗｔ能促融合，但它的突变体ＨＩＶＧｌｕ（２位Ｖ→Ｅ）却不能诱发融合。为了进一步研究多肽结构与功能的关系，我们用荧光及单分子层膜技术研究ＨＩＶｗｔ及ＨＩＶＧｌｕ与脂的相互作用。荧光淬灭实验表明ＨＩＶｗｔ插入带负电磷脂并插入较深；而ＨＩＶＧｌｕ虽然能与带负电脂结合但并不插膜。单层膜实验进一步证实了上述结果：ＨＩＶｗｔ对带负电磷脂ＰＯＰＧ的临界插膜压达到４３ｍＮ／ｍ，而ＨＩＶＧｌｕ的临界插膜压只有３１ｍＮ／ｍ。这提示ＨＩＶｗｔ与单层膜不仅存在静电作用还有较强的疏水作用。结合上述实验结果推测ＨＩＶｗｔ能插入脂膜的酰基链因而容易促发融合；而ＨＩＶＧｌｕ插膜很浅或根本不能入膜从而不能促融合
Our previous experiments demonstrated that the HIV-1 gp41 N-terminal 23 peptide, HIV fusion peptide, can promote fusion, but its mutant HIVGlu (2 V → E) failed to induce fusion. To further investigate the relationship between peptide structure and function, we used fluorescence and monolayers to study the interaction of HIVwt and HIVGlu with lipids. Fluorescence quenching experiments showed that HIVwt was inserted into the negatively charged phospholipid and inserted deeper, whereas HIVGlu, although capable of binding negatively charged lipids, did not intercalate. The monolayer experiment further confirmed the above results: the critical insertion pressure of HIVwt for negatively charged phospholipid POPG reached 43 mN / m, while the critical insertion pressure of HIVGlu was only 31 mN / m. This suggests that HIVwt and monolayers not only have the electrostatic effect but also a strong hydrophobic effect. Combined with the above experimental results suggest that HIVwt can be inserted into the lipid membrane of the acyl chain and thus easy to trigger fusion; and HIVGlu intercalary membrane is very shallow or can not enter the membrane and therefore can not promote fusion