Schoolnik G K, Fernandez R, Tai J Y, Rothbard J, Gotschlich E C
J Exp Med. 1984 May 1;159(5):1351-70. doi: 10.1084/jem.159.5.1351.
The complete amino acid sequence of pilin from gonococcal strain MS11 and the sequence of constant and variable regions from strain R10 pilin have been determined in order to elucidate the structural basis for adherence function, antigenic diversity, and polymeric structure. The MS11 pilin sequence consists of 159 amino acids in a single polypeptide chain with two cysteines in disulfide linkage and serine-bonded phosphate residues. TC-2 (31-111), a soluble monomeric pilus peptide prepared by arginine-specific digestion, bound human endocervical, but not buccal or HeLa cells and therefore is postulated to encompass the receptor binding domain. Variable regions of CNBr-3 appear to confer antigenic diversity and comprise segments in which changes in the position of charged residues occur in hydrophilic, beta-turns. Residues 2-21 and 202-221 of gonococcal pilins and lower eucaryotic actins, respectively, exhibit 50% homology. When these residues are arranged at intervals of 100 degrees of arc on "helical wheels," the identical amino acids comprise a hydrophobic face on one side of the helix. This observation, the hydrophobic character of this region and the tendency for TC-1 (residues 1-30) to aggregate in water, suggest that this stretch interacts with other subunits to stabilize polymeric structure.
已确定淋球菌菌株MS11菌毛蛋白的完整氨基酸序列以及菌株R10菌毛蛋白恒定区和可变区的序列，以阐明黏附功能、抗原多样性和聚合结构的结构基础。MS11菌毛蛋白序列由一条含有两个通过二硫键连接的半胱氨酸和丝氨酸结合磷酸残基的单多肽链中的159个氨基酸组成。TC-2（31-111）是一种通过精氨酸特异性消化制备的可溶性单体菌毛肽，它能与人宫颈细胞结合，但不能与颊细胞或HeLa细胞结合，因此推测其包含受体结合结构域。CNBr-3的可变区似乎赋予了抗原多样性，并且包含带电残基位置在亲水性β转角处发生变化的片段。淋球菌菌毛蛋白的2-21位残基和低等真核肌动蛋白的202-221位残基分别表现出50%的同源性。当这些残基以100度弧的间隔排列在“螺旋轮”上时，相同的氨基酸在螺旋的一侧构成一个疏水表面。这一观察结果、该区域的疏水特性以及TC-1（1-30位残基）在水中聚集的倾向，表明这段序列与其他亚基相互作用以稳定聚合结构。
