STUDY ON THE MEMBRANE INSERTION DEPTH AND ORIENTATION OFHIV-1 FUSION PEPTIDE BY FOURIER TRANSFORMEDINFRARED SPECTORSCOPY
用傅里叶变换红外光谱技术研究HIV-1融合肽的插膜深度与角度

To investigate the mechanism of membrane fusion induced by HIV-1 gp41 N terminal fusion peptide, we studied its membrane insertion state and orientation by H/D exchange and polarized FTIR in acidic POPG and neutral POPC liposomes, respectively. The results indicate that only 11.9% of backbone amide protons of HIVWT in POPG vesicles undergo H/D exchange, whereas 44.6% amide protons are exchangeable for HIVWT in POPC SUV. The average angles of α-helix and β-strand of HIVWT with respect to the POPG bilayer surface are 29±2° and 25±1°, respectively. In the presence of POPC SUV, the average angle between the α-helix of HIVWT and the bilayer surface is 22±1°, and the average angle of β-strand of HIVWT is 26±3°. The membrane insertion state of HIVWT was discussed.