Parge H E, Forest K T, Hickey M J, Christensen D A, Getzoff E D, Tainer J A
Department of Molecular Biology, Scripps Research Institute, La Jolla, California 92037, USA.
Nature. 1995 Nov 2;378(6552):32-8. doi: 10.1038/378032a0.
The crystallographic structure of Neisseria gonorrhoeae pilin, which assembles into the multifunctional pilus adhesion and virulence factor, reveals an alpha-beta roll fold with a striking 85 A alpha-helical spine and an O-linked disaccharide. Key residues stabilize interactions that allow sequence hypervariability, responsible for pilin's celebrated antigenic variation, within disulphide region beta-strands and connections. Pilin surface shape, hydrophobicity and sequence variation constrain pilus assembly to the packing of flat subunit faces against alpha 1 helices. Helical fibre assembly is postulated to form a core of coiled alpha 1 helices banded by beta-sheet, leaving carbohydrate and hypervariable sequence regions exposed to solvent.
淋病奈瑟菌菌毛蛋白的晶体结构可组装成多功能菌毛黏附因子和毒力因子，其呈现出一种α-β折叠结构，带有一条显著的85埃的α螺旋主干和一个O-连接二糖。关键残基稳定了相互作用，使得在二硫键区域的β链和连接部位内允许序列高度可变，这是菌毛蛋白著名的抗原变异的原因。菌毛蛋白的表面形状、疏水性和序列变异将菌毛组装限制为扁平亚基面与α1螺旋的堆积。推测螺旋纤维组装形成由β片层环绕的卷曲α1螺旋核心，使碳水化合物和高度可变序列区域暴露于溶剂中。
