Biomaterial Database

The host outer membrane proteins OmpA and OmpC are associated with the Shigella phage Sf6 virion. 2011

Haiyan Zhao, and Reuben D Sequeira, and Nadezhda A Galeva, and Liang Tang

Department of Molecular Biosciences, University of Kansas, 1200 Sunnyside Avenue, Lawrence, KS 66045, USA. zhaohy@ku.edu

Assembly of dsDNA bacteriophage is a precisely programmed process. Potential roles of host cell components in phage assembly haven't been well understood. It was previously reported that two unidentified proteins were present in bacteriophage Sf6 virion (Casjens et al, 2004, J.Mol.Biol. 339, 379-394, Fig. 2A). Using tandem mass spectrometry, we have identified the two proteins as outer membrane proteins (OMPs) OmpA and OmpC from its host Shigella flexneri. The transmission electron cryo-microscopy structure of Sf6 shows significant density at specific sites at the phage capsid inner surface. This density fit well with the characteristic beta-barrel domains of OMPs, thus may be due to the two host proteins. Locations of this density suggest a role in Sf6 morphogenesis reminiscent of phage-encoded cementing proteins. These data indicate a new, OMP-related phage:host linkage, adding to previous knowledge that some lambdoid bacteriophage genomes contain OmpC-like genes that express phage-encoded porins in the lysogenic state.

UI	MeSH Term	Description	Entries
D001425	Bacterial Outer Membrane Proteins	Proteins isolated from the outer membrane of Gram-negative bacteria.	OMP Proteins,Outer Membrane Proteins, Bacterial,Outer Membrane Lipoproteins, Bacterial
D001435	Bacteriophages	Viruses whose hosts are bacterial cells.	Phages,Bacteriophage,Phage
D012763	Shigella flexneri	A bacterium which is one of the etiologic agents of bacillary dysentery (DYSENTERY, BACILLARY) and sometimes of infantile gastroenteritis.
D014771	Virion	The infective system of a virus, composed of the viral genome, a protein core, and a protein coat called a capsid, which may be naked or enclosed in a lipoprotein envelope called the peplos.	Virus Particle,Viral Particle,Viral Particles,Particle, Viral,Particle, Virus,Particles, Viral,Particles, Virus,Virions,Virus Particles
D046529	Microscopy, Electron, Transmission	Electron microscopy in which the ELECTRONS or their reaction products that pass down through the specimen are imaged below the plane of the specimen.	Electron Diffraction Microscopy,Electron Microscopy, Transmission,Microscopy, Electron Diffraction,Transmission Electron Microscopy,Diffraction Microscopy, Electron,Microscopy, Transmission Electron
D053719	Tandem Mass Spectrometry	A mass spectrometry technique using two (MS/MS) or more mass analyzers. With two in tandem, the precursor ions are mass-selected by a first mass analyzer, and focused into a collision region where they are then fragmented into product ions which are then characterized by a second mass analyzer. A variety of techniques are used to separate the compounds, ionize them, and introduce them to the first mass analyzer. For example, for in GC-MS/MS, GAS CHROMATOGRAPHY-MASS SPECTROMETRY is involved in separating relatively small compounds by GAS CHROMATOGRAPHY prior to injecting them into an ionization chamber for the mass selection.	Mass Spectrometry-Mass Spectrometry,Mass Spectrometry Mass Spectrometry,Mass Spectrometry, Tandem
D018272	Porins	Porins are protein molecules that were originally found in the outer membrane of GRAM-NEGATIVE BACTERIA and that form multi-meric channels for the passive DIFFUSION of WATER; IONS; or other small molecules. Porins are present in bacterial CELL WALLS, as well as in plant, fungal, mammalian and other vertebrate CELL MEMBRANES and MITOCHONDRIAL MEMBRANES.	Pore Protein,Pore Proteins,Porin,Protein, Pore,Proteins, Pore
D020285	Cryoelectron Microscopy	Electron microscopy involving rapid freezing of the samples. The imaging of frozen-hydrated molecules and organelles permits the best possible resolution closest to the living state, free of chemical fixatives or stains.	Electron Cryomicroscopy,Cryo-electron Microscopy,Cryo electron Microscopy,Cryo-electron Microscopies,Cryoelectron Microscopies,Cryomicroscopies, Electron,Cryomicroscopy, Electron,Electron Cryomicroscopies,Microscopies, Cryo-electron,Microscopies, Cryoelectron,Microscopy, Cryo-electron,Microscopy, Cryoelectron