View source for 8wkd


==Connectase T1A C192S mutant from Methanocaldococcus mazei with peptide substrate==
<StructureSection load='8wkd' size='340' side='right'caption='[[8wkd]], [[Resolution|resolution]] 1.98&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8wkd]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Methanosarcina_mazei Methanosarcina mazei]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8WKD OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8WKD FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.98&#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=8wkd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8wkd OCA], [https://pdbe.org/8wkd PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8wkd RCSB], [https://www.ebi.ac.uk/pdbsum/8wkd PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8wkd ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A0A0F8NKN3_METMZ A0A0F8NKN3_METMZ] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Enzyme-catalyzed protein modifications have become invaluable in diverse applications, outperforming chemical methods in terms of precision, conjugation efficiency, and biological compatibility. Despite significant advances in ligases, such as sortase A and OaAEP1, their use in heterogeneous biological environments remains constrained by limited target sequence specificity. In 2021, Lupas' group introduced Connectase, a family of repurposed archaeal proteases for protein ligations, but its low processivity and lack of structural information have impeded further engineering for practical biological and biophysical applications. Here, we present the X-ray crystallographic structures of MmConnectase (Methanococcus maripaludis, MmCET) in both apo and substrate-bound forms. Comparative analysis with its inactive paralogue, MjCET (Methanococcus janaschi), reveals the structural basis of MmCET's high-precision ligation activity. We propose modifications to the N-terminal substrate recognition motifs to suppress MmCET's reversible protease activity, enabling high-precision protein ligations in complex biological environments, such as serum-containing cell cultures. To further demonstrate the enhanced processivity and precision, single-molecule protein unfolding experiments showed that our optimized Connectase, in conjunction with OaAEP1(C247A), can perform stepwise tandem ligations of protein leading to a well-defined protein polymer.

Structural Basis of High-Precision Protein Ligation and Its Application.,Chong KHC, Liu L, Chua R, Chai YT, Lu Z, Liu R, Tan EYJ, Dong J, Khoh YH, Lin J, Zhong FL, Lescar J, Zheng P, Wu B J Am Chem Soc. 2025 Jan 2. doi: 10.1021/jacs.4c10689. PMID:39745918<ref>PMID:39745918</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 8wkd" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Methanosarcina mazei]]
[[Category: Chong HC]]
[[Category: Wu B]]