Proteomics characterization of outer membrane vesicles from the extraintestinal pathogenic Escherichia coli ΔtolR IHE3034 mutant
Proteomics characterization of outer membrane vesicles from the extraintestinal pathogenic Escherichia coli ΔtolR IHE3034 mutant
复制标题
DOI：
10.1074/mcp.m700295-mcp200
复制
发表时间：
2008-03-01
影响因子：
7
通讯作者：
Grandi, Guido
中科院分区：
文献类型：
--
作者：
Scorza, Francesco Berlanda;Doro, Francesco;Grandi, Guido
肠外致病性大肠杆菌是人类和动物中多种侵袭性感染的原因，导致尿路感染、脑膜炎或败血症。在这项研究中，我们把我们的注意力集中在病原体的外膜蛋白的鉴定，考虑到其重要的生物学作用和其作为潜在的预防和治疗干预的目标。为此，我们产生了致病性IHE 3034菌株的Delta tolR突变体，其在培养上清液中自发地释放大量的外膜囊泡。通过二维电泳结合质谱法分析囊泡。分析导致100个蛋白质的鉴定，其中大部分定位于外膜和周质室。有趣的是，基于目前公共数据库中可用的基因组序列，七种鉴定的蛋白质似乎对致病性E。大肠杆菌和肠道细菌，因此是疫苗和药物开发的潜在目标。最后，我们证明了细胞致死膨胀毒素，毒素完全由致病菌产生，释放与囊泡，支持最近提出的细菌囊泡在毒素传递到宿主细胞的作用。总体而言，我们的数据表明，外膜囊泡是一个理想的工具，研究革兰氏阴性菌周质和外膜室，并阐明新的细菌致病机制。
Extraintestinal pathogenic Escherichia coli are the cause of a diverse spectrum of invasive infections in humans and animals, leading to urinary tract infections, meningitis, or septicemia. In this study, we focused our attention on the identification of the outer membrane proteins of the pathogen in consideration of their important biological role and of their use as potential targets for prophylactic and therapeutic interventions. To this aim, we generated a Delta tolR mutant of the pathogenic IHE3034 strain that spontaneously released a large quantity of outer membrane vesicles in the culture supernatant. The vesicles were analyzed by two-dimensional electrophoresis coupled to mass spectrometry. The analysis led to the identification of 100 proteins, most of which are localized to the outer membrane and periplasmic compartments. Interestingly based on the genome sequences available in the current public database, seven of the identified proteins appear to be specific for pathogenic E. coli and enteric bacteria and therefore are potential targets for vaccine and drug development. Finally we demonstrated that the cytolethal distending toxin, a toxin exclusively produced by pathogenic bacteria, is released in association with the vesicles, supporting the recently proposed role of bacterial vesicles in toxin delivery to host cells. Overall, our data demonstrated that outer membrane vesicles represent an ideal tool to study Gram-negative periplasm and outer membrane compartments and to shed light on new mechanisms of bacterial pathogenesis.