1aec

<table><tr><td colspan='2'>[[1aec]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Actch Actch]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1AEC OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1AEC FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=E64:N-[N-[1-HYDROXYCARBOXYETHYL-CARBONYL]LEUCYLAMINO-BUTYL]-GUANIDINE'>E64</scene></td></tr>

<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/Actinidain Actinidain], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.22.14 3.4.22.14] </span></td></tr>

[[https://www.uniprot.org/uniprot/ACTN_ACTCH ACTN_ACTCH]] Cysteine protease responsible for the cleavage of kiwellin into kissper and KiTH.<ref>PMID:18442249</ref>

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== Publication Abstract from PubMed ==

E-64, 1-(L-trans-epoxysuccinylleucylamino)-4-guanidinobutane, is a potent and highly selective irreversible inhibitor of cysteine proteases. The crystal structure of a complex of actinidin and E-64 has been determined at 1.86-A resolution by using the difference Fourier method and refined to an R-factor of 14.5%. The electron density map clearly shows that the C2 atom of the E-64 epoxide ring is covalently bonded to the S atom of the active-site cysteine 25. The charged carboxyl group of E-64 forms four H-bonds with the protein and thus may play an important role in favorably positioning the inhibitor molecule for nucleophilic attack by the active-site thiolate anion. The interaction features between E-64 and actinidin are very similar to those seen in the papain-E-64 complex; however, the amino-4-guanidinobutane group orients differently. The crystals of the actinidin-E-64 complex diffracted much better than the papain-E-64 complex, and consequently the present study provides more precise geometrical information on the binding of the inhibitor. Moreover, this study provides yet another confirmation that the binding of E-64 is at the S subsites and not at the S' subsites as has been previously proposed. The original actinidin structure has been revised using the new cDNA sequence information.

Crystal structure of an actinidin-E-64 complex.,Varughese KI, Su Y, Cromwell D, Hasnain S, Xuong NH Biochemistry. 1992 Jun 9;31(22):5172-6. PMID:1606141<ref>PMID:1606141</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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<div class="pdbe-citations 1aec" style="background-color:#fffaf0;"></div>

[[Category: Actch]]

[[Category: Actinidain]]

[[Category: Varughese, K I]]

[[Category: Hydrolase]]