title: New structural proteins of Halobacterium salinarum gas vesicle revealed by comparative proteomics analysis.
abstract: The Halobacterium salinarum gas vesicle (GV) is an extremely stable intracellular organelle with air trapped inside a proteinaceous membrane. Reported here is a comparative proteomics analysis of GV and GV depleted lysate (GVD) to reveal the membrane structural proteins. Ten proteins encoded by gvp-1 (gvpMLKJIHGFED-1 and gvpACNO-1) and five proteins encoded by gvp-2 (gvpMLKJIHGFED-2 and gvpACNO-2) gene clusters for the biogenesis of spindle- and cylindrical-, respectively, shaped GV were identified by LC-MS/MS. The peptides of GvpA1, I1, J1, A2, and J2 were exclusively identified in purified GV, GvpD1, H1, L1, and F2 only in GVD, and GvpC1, N1, O1, F1, H2, and O2 in both samples. The identification of GvpA1, C1, F1, J1, and A2 in GV is in agreement with their previously known structural function. In addition, the detection of GvpI1, N1, O1, H2, J2, and O2 in GV suggested they are new structural proteins. Among these, the structural role of GvpI1 and N1 in GV was further validated by immuno-detection of protein A-tagged GvpI1 and N1 fusion proteins in purified GV. Thus, LC-MS/MS could reveal at least a half dozen gas vesicle structural proteins in the predominant spindle-shaped GV that may be helpful for studying its biogenesis.
authors.affiliation: Institute of Biotechnology in Medicine, National Yang Ming University, Taipei, Taiwan, Republic of China.
authors.forename: Lichieh Julie
authors.initials: LJ
authors.lastname: Chu
authors.forename: Mengchieh Claire
authors.initials: MC
authors.lastname: Chen
authors.forename: Jocelyn
authors.initials: J
authors.lastname: Setter
authors.forename: Yihsuan Shannon
authors.initials: YS
authors.lastname: Tsai
authors.forename: Hanyin
authors.initials: H
authors.lastname: Yang
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Fang
authors.forename: Ying Sonia
authors.initials: YS
authors.lastname: Ting
authors.forename: Scott A
authors.initials: SA
authors.lastname: Shaffer
authors.forename: Gregory K
authors.initials: GK
authors.lastname: Taylor
authors.forename: Priska D
authors.initials: PD
authors.lastname: von Haller
authors.forename: David R
authors.initials: DR
authors.lastname: Goodlett
authors.forename: Wailap Victor
authors.initials: WV
authors.lastname: Ng
mesh_terms: D019617:Halobacterium salinarum / Q000737:chemistry*; D013058:Mass Spectrometry / Q000379:methods; D010455:Peptides / Q000032:analysis; D011506:Proteins / Q000032:analysis* / Q000235:genetics; D040901:Proteomics / Q000379:methods*; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics
chemical_list: D010455:Peptides; D011506:Proteins; D011993:Recombinant Fusion Proteins; C038524:gas vesicle protein