title: Comprehensive proteomic analysis of Shigella flexneri 2a membrane proteins.
abstract: Shigella flexneri is the causative agent of most shigellosis cases in developing countries. We used different proteolytic enzymes to selectively shave the protruding proteins on the surface of purified bacterial membrane sheets or vesicles, and recovered peptides were subsequently identified using 2-D LC-MS/MS. As a result, a total of 666 proteins were unambiguously assigned, including 159 integral membrane proteins, 35 outer membrane proteins and 114 proteins previously annotated as hypothetical. The former had an average grand average hydrophobicity score of 0.362 and were predicted to separate within a pH range of 4.1-10.6 with molecular mass 8-148 kDa, which represents the largest validated set of integral membrane proteins in this organism to date. A functional classification revealed that a large proportion of the identified proteins were involved in cell envelope biogenesis and energy production and conversion. For the first time, this work provides a global view of the S. flexneri 2a membrane subproteome.
authors.affiliation: State Key Laboratory for Molecular Virology and Genetic Engineering, Institute of Pathogen Biology, CAMS, Beijing 100730, Peoples Republic of China.
authors.forename: Candong
authors.initials: C
authors.lastname: Wei
authors.forename: Jian
authors.initials: J
authors.lastname: Yang
authors.forename: Junping
authors.initials: J
authors.lastname: Zhu
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Zhang
authors.forename: Wenchuan
authors.initials: W
authors.lastname: Leng
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Ying
authors.initials: Y
authors.lastname: Xue
authors.forename: Lilian
authors.initials: L
authors.lastname: Sun
authors.forename: Weijun
authors.initials: W
authors.lastname: Li
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
authors.forename: Qi
authors.initials: Q
authors.lastname: Jin
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000032:analysis*; D002853:Chromatography, Liquid; D015180:Electrophoresis, Gel, Two-Dimensional; D013058:Mass Spectrometry; D008565:Membrane Proteins / Q000032:analysis*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D020543:Proteome / Q000032:analysis*; D012763:Shigella flexneri / Q000737:chemistry* / Q000166:cytology / Q000235:genetics
chemical_list: D001425:Bacterial Outer Membrane Proteins; D008565:Membrane Proteins; D020543:Proteome