PDF(Pubmed)
Abstract：
Burkholderia cepacia complex infections remain life-threatening to cystic fibrosis patients, and due to the limited eradication efficiency of current treatments, novel antimicrobial therapies are urgently needed. Surface proteins are among the best targets to develop new therapeutic strategies since they are exposed to the host\'s immune system. A surface-shaving approach was performed using Burkholderia cenocepacia J2315 to quantitatively compare the relative abundance of surface-exposed proteins (SEPs) expressed by the bacterium when grown under aerobic and microaerophilic conditions. After trypsin incubation of live bacteria and identification of resulting peptides by liquid chromatography coupled with mass spectrometry, a total of 461 proteins with ≥2 unique peptides were identified. Bioinformatics analyses revealed a total of 53 proteins predicted as localized at the outer membrane (OM) or extracellularly (E). Additionally, 37 proteins were predicted as moonlight proteins with OM or E secondary localization. B-cell linear epitope bioinformatics analysis of the proteins predicted to be OM and E-localized revealed 71 SEP moieties with predicted immunogenic epitopes. The protegenicity higher scores of proteins BCAM2761, BCAS0104, BCAL0151, and BCAL0849 point out these proteins as the best antigens for vaccine development. Additionally, 10 of the OM proteins also presented a high probability of playing important roles in adhesion to host cells, making them potential targets for passive immunotherapeutic approaches. The immunoreactivity of three of the OM proteins identified was experimentally demonstrated using serum samples from cystic fibrosis patients, validating our strategy for identifying immunoreactive moieties from surface-exposed proteins of potential interest for future immunotherapies development.
摘要：
洋葱伯克霍尔德菌感染仍然威胁着囊性纤维化患者的生命，由于目前治疗的根除效率有限，迫切需要新的抗菌疗法。表面蛋白是开发新的治疗策略的最佳目标之一，因为它们暴露于宿主的免疫系统。使用伯克霍尔德氏菌J2315进行了表面剃刮方法，以定量比较在需氧和微需氧条件下生长时细菌表达的表面暴露蛋白（SEP）的相对丰度。胰蛋白酶孵育活细菌并通过液相色谱与质谱联用鉴定所得肽后，共鉴定出461种具有≥2种独特肽的蛋白质.生物信息学分析显示，总共有53种蛋白质被预测位于外膜（OM）或细胞外（E）。此外,预测37个蛋白为具有OM或E二级定位的月光蛋白。预测为OM和E定位的蛋白质的B细胞线性表位生物信息学分析揭示了具有预测的免疫原性表位的71个SEP部分。蛋白质BCAM2761，BCAS0104，BCAL0151和BCAL0849的蛋白原性得分较高，指出这些蛋白质是疫苗开发的最佳抗原。此外,其中10种OM蛋白也很有可能在与宿主细胞的粘附中起重要作用，使它们成为被动免疫治疗方法的潜在目标。使用囊性纤维化患者的血清样品实验证明了所鉴定的三种OM蛋白的免疫反应性，验证我们从表面暴露的蛋白质中鉴定免疫反应性部分的策略，这些蛋白质对未来的免疫疗法开发具有潜在的兴趣。
