第94回日本細菌学会総会

講演情報

オンデマンド口頭発表(ODP)

6 病原因子と生体防御

[ODP6B] b. 毒素・エフェクター・生理活性物質

[ODP-132] 百日咳菌の浮遊菌およびバイオフィルム形成菌から分泌されるメンブレンベシクルに含まれる病原因子の解析

○花輪 智子1,蒲地 一成2,桑江 朝臣3,阿部 章夫3,米澤 英雄1,大崎 敬子1,北条 史4,神谷 茂1,三戸部 治郎1 (1杏林大・医・感染症,2感染研・細菌第2部,3北里大・院・感染制御科学府・分子細菌,4杏林大・医・実験動物施設)

Background and Objective: Efficacy of the pertussis vaccine is diminishing from approximately 10 years after vaccination, and the strains escaping from vaccine pressure have emerged. Therefore, it is necessary to develop new vaccine. Membrane vesicles (MVs) are vesicles with a diameter of 10-400 μm that are released by bacteria, and are possible candidate for vaccine component. However, spontaneously secreting MVs have not been sufficiently investigated. In this study, we conducted a proteomic analysis to compare the proteins in MVs secreted from planktonic and biofilm-forming bacteria.
Materials and Methods: MVs were collected by ultracentrifugation of the filtered culture supernatant of B. pertussis. After purification by OptiPrep density gradient centrifugation, MVs were analyzed by Nano LC-MS/MS using Proteome Discoverer 2.4 (Thermo Fisher Scientific).
Results and Discussion: Complement inhibitors such as Vag8 and BrkA were found in MVs derived from both planktonic bacteria and biofilm. Virulence associated factors, FimB and BopD, were specifically detected in the MVs from planktonic bacteria. On the other hand, filamentous hemagglutinin, adenylate cyclase toxin, FhaS and SphB1 were abundant in biofilm-derived MVs. These virulence associated factors are relating to adhesion and colonization. Accordingly, biofilm-derived MVs probably have some roles in the colonization.