Structural highlights
Function
[J_BPPHX] Mediates ssDNA packaging into virion, it locates to the internal surface of the capsid, thereby displacing the internal scaffolding protein B during virion formation. Additionally, protein J plays a role in viral attachment to the host cell. [G_BPPHX] Attaches the circulating virion to the bacterial lipopolysaccharides which serve as receptor for the virus. Determines the phage host-range. Probably triggers with protein H the injection of the phage DNA into the host cytoplasm upon conformational changes induced by the interaction with host lipopolysaccharides.[1] [2] [F_BPPHX] Assembles to form an icosahedral capsid with a T=1 symmetry, about 30 nm in diameter, and consisting of 60 capsid proteins F.[3]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The mechanism of DNA ejection, viral assembly and evolution are related to the structure of bacteriophage phi X174. The F protein forms a T = 1 capsid whose major folding motif is the eight-stranded antiparallel beta barrel found in many other icosahedral viruses. Groups of 5 G proteins form 12 dominating spikes that enclose a hydrophilic channel containing some diffuse electron density. Each G protein is a tight beta barrel with its strands running radially outwards and with a topology similar to that of the F protein. The 12 'pilot' H proteins per virion may be partially located in the putative ion channel. The small, basic J protein is associated with the DNA and is situated in an interior cleft of the F protein. Tentatively, there are three regions of partially ordered DNA structure,
Atomic structure of single-stranded DNA bacteriophage phi X174 and its functional implications.,McKenna R, Xia D, Willingmann P, Ilag LL, Krishnaswamy S, Rossmann MG, Olson NH, Baker TS, Incardona NL Nature. 1992 Jan 9;355(6356):137-43. PMID:1370343[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Inagaki M, Tanaka A, Suzuki R, Wakashima H, Kawaura T, Karita S, Nishikawa S, Kashimura N. Characterization of the binding of spike H protein of bacteriophage phiX174 with receptor lipopolysaccharides. J Biochem. 2000 Apr;127(4):577-83. PMID:10739948
- ↑ Inagaki M, Kawaura T, Wakashima H, Kato M, Nishikawa S, Kashimura N. Different contributions of the outer and inner R-core residues of lipopolysaccharide to the recognition by spike H and G proteins of bacteriophage phiX174. FEMS Microbiol Lett. 2003 Sep 26;226(2):221-7. PMID:14553915
- ↑ Hafenstein S, Fane BA. phi X174 genome-capsid interactions influence the biophysical properties of the virion: evidence for a scaffolding-like function for the genome during the final stages of morphogenesis. J Virol. 2002 Jun;76(11):5350-6. PMID:11991963
- ↑ McKenna R, Xia D, Willingmann P, Ilag LL, Krishnaswamy S, Rossmann MG, Olson NH, Baker TS, Incardona NL. Atomic structure of single-stranded DNA bacteriophage phi X174 and its functional implications. Nature. 1992 Jan 9;355(6356):137-43. PMID:1370343 doi:http://dx.doi.org/10.1038/355137a0
