View source for 2jub


==Solution structure of IPI*==
<StructureSection load='2jub' size='340' side='right'caption='[[2jub]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2jub]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_virus_T4 Escherichia virus T4]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2JUB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2JUB FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2jub FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2jub OCA], [https://pdbe.org/2jub PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2jub RCSB], [https://www.ebi.ac.uk/pdbsum/2jub PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2jub ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/IPI1_BPT4 IPI1_BPT4] Internal protein I is one of four proteins in a complex that functions in bacteriophage head maturation.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Phage T4 protects its DNA from the two-gene-encoded gmrS/gmrD (glucose-modified hydroxymethylcytosine restriction endonuclease) CT of pathogenic Escherichia coli, CT596, by injecting several hundred copies of the 76-amino-acid-residue nuclease inhibitor, IPI*, into the infected host. Here, the three-dimensional solution structure of mature IPI* is reported as determined by nuclear magnetic resonance techniques using 1290 experimental nuclear Overhauser effect and dipolar coupling constraints ( approximately 17 constraints per residue). Close examination of this oblate-shaped protein structure reveals a novel fold consisting of two small beta-sheets (beta1: B1 and B2; beta2: B3-B5) flanked at the N- and C-termini by alpha-helices (H1 and H2). Such a fold is very compact in shape and allows ejection of IPI* through the narrow 30-A portal and tail tube apertures of the virion without unfolding. Structural and dynamic measurements identify an exposed hydrophobic knob that is a putative gmrS/gmrD-binding site. A single gene from the uropathogenic E. coli UT189, which codes for a gmrS/gmrD-like UT fusion enzyme (with approximately 90% identity to the heterodimeric CT enzyme), has evolved IPI* inhibitor immunity. Analysis of the gmrS/gmrD restriction endonuclease enzyme family and its IPI* family phage antagonists reveals an evolutionary pathway that has elaborated a surprisingly diverse and specifically fitted set of coevolving attack and defense structures.

Restriction endonuclease inhibitor IPI* of bacteriophage T4: a novel structure for a dedicated target.,Rifat D, Wright NT, Varney KM, Weber DJ, Black LW J Mol Biol. 2008 Jan 18;375(3):720-34. Epub 2007 Nov 1. PMID:18037438<ref>PMID:18037438</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 2jub" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia virus T4]]
[[Category: Large Structures]]
[[Category: Black LW]]
[[Category: Rifat D]]
[[Category: Varney KM]]
[[Category: Weber DJ]]
[[Category: Wright NT]]