View source for 9ha2


==Pooled 50S subunit C_(L22)- precursor states supplemented with Api137 - Alternative PET exit Api137==
<StructureSection load='9ha2' size='340' side='right'caption='[[9ha2]], [[Resolution|resolution]] 4.17&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9ha2]] is a 10 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9HA2 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9HA2 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 4.17&#8491;</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=9ha2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9ha2 OCA], [https://pdbe.org/9ha2 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9ha2 RCSB], [https://www.ebi.ac.uk/pdbsum/9ha2 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9ha2 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/RL3_ECOLI RL3_ECOLI] One of two assembly inititator proteins, it binds directly near the 3'-end of the 23S rRNA, where it nucleates assembly of the 50S subunit.[HAMAP-Rule:MF_01325_B]
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The proline-rich antimicrobial designer peptide Api137 inhibits protein expression in bacteria by binding simultaneously to the ribosomal polypeptide exit tunnel and the release factor (RF), depleting the cellular RF pool and leading to ribosomal arrest at stop codons. This study investigates the additional effect of Api137 on the assembly of ribosomes using an Escherichia coli reporter strain expressing one ribosomal protein per 30S and 50S subunit tagged with mCherry and EGFP, respectively. Separation of cellular extracts derived from cells exposed to Api137 in a sucrose gradient reveals elevated levels of partially assembled and not fully matured precursors of the 50S subunit (pre-50S). High-resolution structures obtained by cryogenic electron microscopy demonstrate that a large proportion of pre-50S states are missing up to five proteins (uL22, bL32, uL29, bL23, and uL16) and have misfolded helices in 23S rRNA domain IV. These data suggest a second mechanism for Api137, wherein it disrupts 50S subunit assembly by inducing the formation of misfolded precursor particles potentially incapable of evolving into active ribosomes, suggesting a bactericidal mechanism.

The proline-rich antimicrobial peptide Api137 disrupts large ribosomal subunit assembly and induces misfolding.,Lauer SM, Gasse J, Krizsan A, Reepmeyer M, Sprink T, Nikolay R, Spahn CMT, Hoffmann R Nat Commun. 2025 Jan 10;16(1):567. doi: 10.1038/s41467-025-55836-8. PMID:39794318<ref>PMID:39794318</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9ha2" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Lauer S]]
[[Category: Nikolay R]]
[[Category: Spahn CMT]]