title: Quantitative analysis of Shigella flexneri protein expression under acid stress.
abstract: As an important foodborne pathogen, Shigella flexneri can cause widespread enteric infection with bacteria as few as hundreds. This is, at least in part, attributed to its robust anti-acid strategies because passage through the highly acidic human digestive tract is a prerequisite for successful bacterial infection. Nevertheless, our understanding of these mechanisms and the impact of acid stress on Shigella protein expression still remains largely incomplete. Herein we conducted a proteomic survey of Shigella spp. under acid stress. Out of 1754 protein identifications, we found 131 altered proteins, most of which were down-regulated, including virulence factors and cell envelope proteins. Rather, many metabolic enzymes and pyrimidine/amino acid biosynthesis proteins were up-regulated. In addition to induction of many known anti-acid systems, we also found marked increase of 2-oxoglutarate dehydrogenase (SucAB), a metabolic enzyme in the tricarboxylic acid cycle. Importantly, overproduction of this enzyme significantly enhanced Shigella acid resistance and hence SucAB-mediated metabolic pathways may represent novel anti-acid strategies.
authors.affiliation: Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China.
authors.forename: Kaiwen
authors.initials: K
authors.lastname: Yu
authors.affiliation: Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China.
authors.forename: Fan
authors.initials: F
authors.lastname: Zhou
authors.affiliation: Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China.
authors.forename: Jiezhang
authors.initials: J
authors.lastname: Jiang
authors.affiliation: Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China.
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China.
authors.forename: Mo
authors.initials: M
authors.lastname: Hu
authors.affiliation: Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, P. R. China.
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Liu
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis* / Q000378:metabolism; D002853:Chromatography, Liquid; D002952:Citric Acid Cycle; D006863:Hydrogen-Ion Concentration; D007655:Ketoglutarate Dehydrogenase Complex / Q000378:metabolism; D053858:Metabolic Networks and Pathways; D040901:Proteomics / Q000379:methods*; D012763:Shigella flexneri / Q000737:chemistry / Q000378:metabolism* / Q000472:pathogenicity; D013312:Stress, Physiological / Q000502:physiology*; D053719:Tandem Mass Spectrometry
chemical_list: D001426:Bacterial Proteins; D007655:Ketoglutarate Dehydrogenase Complex
keywords: Acid resistance; Acid stress; Protein expression; Shigella flexneri