Spinola S M, Griffiths G E, Shanks K L, Blake M S
Department of Medicine, School of Medicine, State University of New York, Buffalo 14215.
Infect Immun. 1993 Apr;61(4):1346-51. doi: 10.1128/iai.61.4.1346-1351.1993.
Haemophilus ducreyi contains a major outer membrane protein (MOMP) whose apparent molecular weight is 39,000 to 42,000 for all strains tested. Two monoclonal antibodies (MAbs), designated 9D12 and 2C7, bound to the MOMP for all strains of H. ducreyi tested. As reported previously, MAb 9D12 was H. ducreyi specific (E. J. Hansen and T. A. Loftus, Infect. Immun. 44:196-198, 1984). MAb 2C7 bound to all members of the family Pasteurellaceae tested, suggesting that the MAbs bound to distinct epitopes on the MOMP. The MOMP was purified by extraction of whole cells with Zwittergent and ion-exchange chromatography. A peak eluted from a cation-exchange column contained three bands. All three species bound both MAbs, and the fraction yielded a single N-terminal amino acid sequence, suggesting that the bands represented different conformations of the MOMP. The MOMP was heat modifiable, contained two cysteine residues, and was cationic at pH 8.0, features not usually associated with classical porin proteins. The N-terminal amino acid sequence and total amino acid content of the MOMP were homologous to the OmpA proteins of members of the family Enterobacteriaceae and the OmpA-like protein of Actinobacillus actinomycetemcomitans. An OmpA-specific polyclonal serum bound to the MOMP, and MAb 2C7 bound to Haemophilus influenzae protein 5, an OmpA-like protein, indicating that the MOMP was antigenically related to OmpA. These data indicated that the most abundant protein in the outer membrane of H. ducreyi was not a classical porin and belonged to the OmpA family of proteins.
杜克雷嗜血杆菌含有一种主要外膜蛋白（MOMP），对于所有测试菌株，其表观分子量为39000至42000。两种单克隆抗体（MAb），命名为9D12和2C7，与所有测试的杜克雷嗜血杆菌菌株的MOMP结合。如先前报道，单克隆抗体9D12具有杜克雷嗜血杆菌特异性（E. J. 汉森和T. A. 洛夫特斯，《感染与免疫》44:196 - 198，1984年）。单克隆抗体2C7与所有测试的巴斯德菌科成员结合，表明这些单克隆抗体与MOMP上不同的表位结合。通过用两性离子去污剂提取全细胞并进行离子交换色谱法纯化MOMP。从阳离子交换柱洗脱的一个峰含有三条带。所有这三种条带都与两种单克隆抗体结合，并且该级分产生单一的N端氨基酸序列，表明这些条带代表MOMP的不同构象。MOMP可被热修饰，含有两个半胱氨酸残基，并且在pH 8.0时呈阳离子性，这些特征通常与经典孔蛋白无关。MOMP的N端氨基酸序列和总氨基酸含量与肠杆菌科成员的OmpA蛋白以及伴放线放线杆菌的OmpA样蛋白同源。一种OmpA特异性多克隆血清与MOMP结合，并且单克隆抗体2C7与流感嗜血杆菌蛋白5（一种OmpA样蛋白）结合，表明MOMP与OmpA在抗原性上相关。这些数据表明，杜克雷嗜血杆菌外膜中最丰富的蛋白不是经典孔蛋白，属于OmpA蛋白家族。
