Cutler C W, Eke P I, Genco C A, Van Dyke T E, Arnold R R
Department of Biomedical Sciences and Periodontics, Baylor College of Dentistry, Dallas, Texas, USA.
Infect Immun. 1996 Jun;64(6):2282-7. doi: 10.1128/iai.64.6.2282-2287.1996.
Previous studies have shown that the physical, biochemical, and antigenic properties of the bacterial outer membrane are profoundly influenced by the growth environment. In the present study, the effects of growth in hemin-replete (H+) and hemin-depleted (H-) media on the lipopolysaccharide (LPS) of the oral pathogen Porphyromonas gingivalis were investigated. Our studies show that LPS from P. gingivalis cultured in H+ media (H+LPS) expressed additional low-molecular-mass antigens, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot (immunoblot) analysis. Particularly evident was a 26-kDa antigen (26 LPSC) that was lost from the LPS upon transfer of P. gingivalis into H- media. The loss of the 26 LPSC was accompanied by a marked reduction in the hemin-binding capacity of the LPS. The 26 LPSC was refractory to Coomassie blue staining and proteinase K digestion. H+LPS from strain W50/BE1, a nonpigmented pleiotropic strain, lacked the 26 LPSC and did not bind hemin. Polyclonal antiserum raised to whole-cell antigens of P. gingivalis A7436, W83, and HG405 grown in H+ media, but not in H- media, recognized the 26 LPSC in the purified H+LPS from any of the three strains. The immunoreactivities of sera from humans with (n = 24) or without (n = 25) periodontitis to the 26 LPSC and other H+LPS determinants were analyzed by Western blot. Overall, 75% of adult periodontitis patient sera reacted with multiple bands in the H+LPS stepladder, particularly in the range of 14 to 27 kDa. In contrast, only 20% of control sera reacted faintly with H+LPS bands in the range 27 to 34 kDa. The 26 LPSC was recognized by over 40% of sera from adult patients with periodontitis and none of the healthy control sera. Taken together, these results suggest that the antigenicity and hemin-binding properties of P. gingivalis LPS can be modified by growth in H+ media.
先前的研究表明，细菌外膜的物理、生化和抗原特性会受到生长环境的深刻影响。在本研究中，我们调查了在富含血红素（H +）和缺乏血红素（H -）的培养基中生长对口腔病原体牙龈卟啉单胞菌脂多糖（LPS）的影响。我们的研究表明，通过十二烷基硫酸钠 - 聚丙烯酰胺凝胶电泳和蛋白质印迹（免疫印迹）分析确定，在H +培养基中培养的牙龈卟啉单胞菌的LPS（H + LPS）表达了额外的低分子量抗原。特别明显的是一种26 kDa的抗原（26 LPSC），当牙龈卟啉单胞菌转移到H -培养基中时，该抗原从LPS中消失。26 LPSC的消失伴随着LPS血红素结合能力的显著降低。26 LPSC对考马斯亮蓝染色和蛋白酶K消化具有抗性。来自非色素多效性菌株W50/BE1的H + LPS缺乏26 LPSC且不结合血红素。针对在H +培养基中而非H -培养基中生长的牙龈卟啉单胞菌A7436、W83和HG405的全细胞抗原产生的多克隆抗血清，识别来自这三种菌株中任何一种的纯化H + LPS中的26 LPSC。通过蛋白质印迹分析了患有（n = 24）或未患有（n = 25）牙周炎的人类血清对26 LPSC和其他H + LPS决定簇的免疫反应性。总体而言，75%的成人牙周炎患者血清与H + LPS阶梯中的多条带发生反应，特别是在14至27 kDa范围内。相比之下，只有20%的对照血清与27至34 kDa范围内的H + LPS条带发生微弱反应。超过40%的成人牙周炎患者血清识别26 LPSC，而健康对照血清均未识别。综上所述，这些结果表明牙龈卟啉单胞菌LPS的抗原性和血红素结合特性可通过在H +培养基中生长而改变。
