Caldwell H D, Kromhout J, Schachter J
Infect Immun. 1981 Mar;31(3):1161-76. doi: 10.1128/iai.31.3.1161-1176.1981.
Elementary bodies (EB) of Chlamydia trachomatis serotypes C, E, and L2 were extrinsically radioiodinated, and whole-cell lysates of these serotypes were compared by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Autoradiography of the polypeptide profiles identified a major surface protein with an apparent subunit molecular weight of 39,500 that was common to each C. trachomatis serotype. The abilities of nonionic (Triton X-100), dipolar ionic (Zwittergent TM-314), mild (sodium deoxycholate and sodium N-lauroyl sarcosine), and strongly anionic (SDS) detergents to extract this protein from intact EB of the L2 serotype were investigated by SDS-PAGE analysis of the soluble and insoluble fractions obtained after each detergent treatment. Only SDS readily extracted this protein from intact EB. Sarkosyl treatment selectively solubilized the majority of other EB proteins, leaving the 39,500-dalton protein associated with the Sarkosyl-insoluble fraction. Ultrastructural studies of the Sarkosyl-insoluble EB pellet showed it to consist of empty EB particles possessing an apparently intact outer membrane. No structural evidence for a peptidoglycan-like cell wall was found. Morphologically these chlamydial outer membrane complexes (COMC) resembled intact chlamydial EB outer membranes. The 39,500-dalton outer membrane protein was quantitatively extracted from COMC by treating them with 2% SDS at 60 degrees C. This protein accounted for 61% of the total COMC-associated protein, and its extraction resulted in a concomitant loss of the COMC membrane structure and morphology. The soluble extract obtained from SDS-treated COMC was adsorbed to a hydroxylapatite column and eluted with a linear sodium phosphate gradient. The 39,500-dalton protein was eluted from the column as a single peak at a phosphate concentration of approximately 0.3 M. The eluted protein was nearly homogeneous by SDS-PAGE and appeared free of contaminating carbohydrate, glycolipid, and nucleic acid. Hyperimmune mouse antiserum prepared against the 39,500-dalton protein from serotype L2 reacted with C. trachomatis serotypes Ba, E, D, K, L1, L2, and L3 by indirect immunofluorescence with EB but failed to react with serotypes A, B, C, F, G, H, I, and J, with the C. trachomatis mouse pneumonitis strain, or with the C. psittaci feline pneumonitis, guinea pig inclusion conjunctivitis, or 6BC strains. Thus, the 39,500-dalton major outer membrane protein is a serogroup antigen of C. trachomatis organisms.
沙眼衣原体C、E和L2血清型的原体（EB）经体外放射性碘化，通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）比较这些血清型的全细胞裂解物。多肽图谱的放射自显影片鉴定出一种主要表面蛋白，其表观亚基分子量为39,500，是每种沙眼衣原体血清型共有的。通过对每种去污剂处理后获得的可溶和不溶部分进行SDS-PAGE分析，研究了非离子（Triton X-100）、两性离子（Zwittergent TM-314）、温和（脱氧胆酸钠和N-月桂酰肌氨酸钠）和强阴离子（SDS）去污剂从L2血清型完整EB中提取该蛋白的能力。只有SDS能轻易地从完整EB中提取该蛋白。 Sarkosyl处理选择性地溶解了大多数其他EB蛋白，使39,500道尔顿的蛋白与Sarkosyl不溶部分相关联。对Sarkosyl不溶EB沉淀的超微结构研究表明，它由具有明显完整外膜的空EB颗粒组成。未发现类肽聚糖细胞壁的结构证据。从形态学上看，这些衣原体外膜复合物（COMC）类似于完整的衣原体EB外膜。通过在60℃下用2% SDS处理，从COMC中定量提取了39,500道尔顿的外膜蛋白。该蛋白占与COMC相关的总蛋白的61%，其提取导致COMC膜结构和形态的相应丧失。从SDS处理的COMC中获得的可溶提取物吸附到羟基磷灰石柱上，并用线性磷酸钠梯度洗脱。39,500道尔顿的蛋白在磷酸盐浓度约为0.3 M时作为单峰从柱上洗脱。通过SDS-PAGE分析，洗脱的蛋白几乎是纯的，并且似乎没有碳水化合物、糖脂和核酸污染。用针对L2血清型39,500道尔顿蛋白制备的超免疫小鼠抗血清，通过与EB的间接免疫荧光法与沙眼衣原体Ba、E、D、K、L1、L2和L3血清型反应，但不与A、B、C、F、G、H、I和J血清型、沙眼衣原体小鼠肺炎菌株或鹦鹉热衣原体猫肺炎、豚鼠包涵体结膜炎或6BC菌株反应。因此，39,500道尔顿的主要外膜蛋白是沙眼衣原体生物体的一种血清群抗原。
