Shon K J, Kim Y, Colnago L A, Opella S J
Department of Chemistry, University of Pennsylvania, Philadelphia 19104.
Science. 1991 May 31;252(5010):1303-5. doi: 10.1126/science.1925542.
Filamentous bacteriophage coat protein undergoes a remarkable structural transition during the viral assembly process as it is transferred from the membrane environment of the cell, where it spans the phospholipid bilayer, to the newly extruded virus particles. Nuclear magnetic resonance (NMR) studies show the membrane-bound form of the 46-residue Pf1 coat protein to be surprisingly complex with five distinct regions. The secondary structure consists of a long hydrophobic helix (residues 19 to 42) that spans the bilayer and a short amphipathic helix (residues 6 to 13) parallel to the plane of the bilayer. The NH2-terminus (residues 1 to 5), the COOH-terminus (residues 43 to 46), and residues 14 to 18 connecting the two helices are mobile. By comparing the structure and dynamics of the membrane-bound coat protein with that of the viral form as determined by NMR and neutron diffraction, essential features of assembly process can be identified.
丝状噬菌体外壳蛋白在病毒组装过程中经历了显著的结构转变，因为它从细胞的膜环境（在那里它跨越磷脂双层）转移到新挤出的病毒颗粒中。核磁共振（NMR）研究表明，46个残基的Pf1外壳蛋白的膜结合形式令人惊讶地复杂，有五个不同的区域。二级结构由一个跨越双层的长疏水螺旋（残基19至42）和一个平行于双层平面的短两亲螺旋（残基6至13）组成。NH2末端（残基1至5）、COOH末端（残基43至46）以及连接两个螺旋的残基14至18是可移动的。通过比较由NMR和中子衍射确定的膜结合外壳蛋白与病毒形式的结构和动力学，可以确定组装过程的基本特征。
