title: Flagella proteins contribute to the production of outer membrane vesicles from Escherichia coli W3110.
abstract: Gram-negative bacteria, including Escherichia coli, release outer membrane vesicles (OMVs) that are derived from the bacterial outer membrane. OMVs contribute to bacterial cell-cell communications and host-microbe interactions by delivering components to locations outside the bacterial cell. In order to explore the molecular machinery involved in OMV biogenesis, the role of a major OMV protein was examined in the production of OMVs from E. coli W3110, which is a widely used standard E. coli K-12 strain. In addition to OmpC and OmpA, which are used as marker proteins for OMVs, an analysis of E. coli W3110 OMVs revealed that they also contain abundant levels of FliC, which is also known as flagellin. A membrane-impermeable biotin-labeling reagent did not label FliC in intact OMVs, but labeled FliC in sonically disrupted OMVs, suggesting that FliC is localized in the lumen of OMV. Compared to the parental strain expressing wild-type fliC, an E. coli strain with a fliC-null mutation produced reduced amounts of OMVs based on both protein and phosphate levels. In addition, an E. coli W3110-derived strain with a null-mutation in flgK, which encodes flagellar hook-associated protein that is essential along with FliC for flagella synthesis, also produced fewer OMVs than the parental strain. Taken together, these results indicate that the ability to form flagella, including the synthesis of flagella proteins, affects the production of E. coli W3110 OMVs.
authors.affiliation: Faculty of Pharmaceutical Sciences, Doshisha Women's College, Kyotanabe, Kyoto 610-0395, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Manabe
authors.forename: Mayu
authors.initials: M
authors.lastname: Kato
authors.forename: Takayuki
authors.initials: T
authors.lastname: Ueno
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Kawasaki
mesh_terms: D021961:Cell Membrane Structures / Q000378:metabolism*; D004926:Escherichia coli / Q000254:growth & development / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000378:metabolism*; D005407:Flagella / Q000378:metabolism*
chemical_list: D029968:Escherichia coli Proteins
keywords: Bacteria; Biogenesis; LPS; MALDI-TOF; Membrane; OMVs; PAGE; Proteomics; SDS; lipopolysaccharide; matrix-assisted laser desorption ionization–time of flight; outer membrane vesicles; polyacrylamide gel electrophoresis; sodium dodecyl sulfate