title: Comparative proteomic analysis of outer membrane vesicles from Shigella flexneri under different culture conditions.
abstract: The production of outer membrane vesicles (OMVs) is a common and regulated process of gram-negative bacteria. Nonetheless, the processes of Shigella flexneri OMV production still remain unclear. S. flexneri is the causative agent of endemic shigellosis in developing countries. The Congo red binding of strains is associated with increased infectivity of S. flexneri. Therefore, understanding the modulation pattern of OMV protein expression induced by Congo red will help to elucidate the bacterial pathogenesis. In the present study, we investigated the proteomic composition of OMVs and the change in OMV protein expression induced by Congo red using mTRAQ-based quantitative comparative proteomics. mTRAQ labelling increased the confidence in protein identification, and 148 total proteins were identified in S. flexneri-derived OMVs. These include a variety of important virulence factors, including Ipa proteins, TolC family, murein hydrolases, and members of the serine protease autotransporters of Enterobacteriaceae (SPATEs) family. Among the identified proteins, 28 and five proteins are significantly up- and down-regulated in the Congo red-induced OMV, respectively. Additionally, by comprehensive comparison with previous studies focused on DH5a-derived OMV, we identified some key node proteins in the protein-protein interaction network that may be involved in OMV biogenesis and are common to all gram-negative bacteria.
authors.affiliation: MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Chen
authors.affiliation: MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China.
authors.forename: Liguo
authors.initials: L
authors.lastname: Liu
authors.affiliation: MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China.
authors.forename: Hua
authors.initials: H
authors.lastname: Fu
authors.affiliation: MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China. Electronic address: weicando@ipbcams.ac.cn.
authors.forename: Candong
authors.initials: C
authors.lastname: Wei
authors.affiliation: MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China. Electronic address: zdsys@vip.sina.com.
authors.forename: Qi
authors.initials: Q
authors.lastname: Jin
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D008565:Membrane Proteins / Q000378:metabolism*; D020543:Proteome / Q000378:metabolism*; D022142:Secretory Vesicles / Q000378:metabolism* / Q000648:ultrastructure; D012763:Shigella flexneri / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D001425:Bacterial Outer Membrane Proteins; D008565:Membrane Proteins; D020543:Proteome
keywords: Comparative proteomics; Outer membrane vesicle; Quantitative labeling; Shigella flexneri 2a; Virulence