5bu5
From Proteopedia
(Difference between revisions)
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<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5bu5 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5bu5 OCA], [http://pdbe.org/5bu5 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5bu5 RCSB], [http://www.ebi.ac.uk/pdbsum/5bu5 PDBsum]</span></td></tr> | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5bu5 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5bu5 OCA], [http://pdbe.org/5bu5 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5bu5 RCSB], [http://www.ebi.ac.uk/pdbsum/5bu5 PDBsum]</span></td></tr> | ||
</table> | </table> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | Bacterial viruses of the P22-like family encode a specialized tail needle essential for genome stabilization after DNA-packaging and implicated in Gram-negative cell envelope penetration. The atomic structure of P22 tail needle (gp26) crystallized at acidic pH reveals a slender fiber containing an N-terminal trimer-of-hairpins tip. Though the length and composition of tail needles vary significantly in Podoviridae, unexpectedly, the amino acid sequence of the N-terminal tip is exceptionally conserved in more than two hundred genomes of P22-like phages and prophages. In this paper, we used X-ray crystallography and EM to investigate the neutral pH structure of three tail needles from bacteriophage P22, HK620 and Sf6. In all cases, we found the N-terminal tip is poorly structured, in stark contrast to the compact trimer-of-hairpins seen in gp26 crystallized at acidic pH. Hydrogen/deuterium exchange mass spectrometry, limited proteolysis, circular dichroism spectroscopy and gel filtration chromatography revealed that the N-terminal tip is highly dynamic in solution and unlikely to adopt a stable trimeric conformation at physiological pH. This is supported by the cryo-EM reconstruction of P22 mature virion tail, where the density of gp26 N-terminal tip is incompatible with a trimer-of-hairpins. We propose the tail needle N-terminal tip exists in two conformations: a pre-ejection extended conformation, which seals the portal vertex after genome-packaging and a post-ejection trimer-of-hairpins that form upon its release from the virion. The conformational plasticity of the tail needle N-terminal tip is built in the amino acid sequence, explaining its extraordinary conservation in nature. | ||
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| + | Structural plasticity of the protein plug that traps newly packaged genomes in podoviridae virions.,Bhardwaj A, Sankhala RS, Olia AS, Brooke D, Casjens SR, Taylor DJ, Prevelige PE Jr, Cingolani G J Biol Chem. 2015 Nov 16. pii: jbc.M115.696260. PMID:26574546<ref>PMID:26574546</ref> | ||
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| + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| + | </div> | ||
| + | <div class="pdbe-citations 5bu5" style="background-color:#fffaf0;"></div> | ||
| + | == References == | ||
| + | <references/> | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
Revision as of 10:00, 2 December 2015
HK620 Tail Needle crystallized at pH 9 (crystal form I)
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