1a16

<StructureSection load='1a16' size='340' side='right' caption='[[1a16]], [[Resolution|resolution]] 2.30&Aring;' scene=''>

<table><tr><td colspan='2'>[[1a16]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1A16 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1A16 FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=LEU:LEUCINE'>LEU</scene>, <scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</scene>, <scene name='pdbligand=PRO:PROLINE'>PRO</scene></td></tr>

<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Xaa-Pro_aminopeptidase Xaa-Pro aminopeptidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.11.9 3.4.11.9] </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=1a16 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1a16 OCA], [http://pdbe.org/1a16 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1a16 RCSB], [http://www.ebi.ac.uk/pdbsum/1a16 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=1a16 ProSAT]</span></td></tr>

<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/a1/1a16_consurf.spt"</scriptWhenChecked>

<div style="background-color:#fffaf0;">

== Publication Abstract from PubMed ==

The structure of the proline-specific aminopeptidase (EC 3.4.11.9) from Escherichia coli has been solved and refined for crystals of the native enzyme at a 2.0-A resolution, for a dipeptide-inhibited complex at 2.3-A resolution, and for a low-pH inactive form at 2.7-A resolution. The protein crystallizes as a tetramer, more correctly a dimer of dimers, at both high and low pH, consistent with observations from analytical ultracentrifuge studies that show that the protein is a tetramer under physiological conditions. The monomer folds into two domains. The active site, in the larger C-terminal domain, contains a dinuclear manganese center in which a bridging water molecule or hydroxide ion appears poised to act as the nucleophile in the attack on the scissile peptide bond of Xaa-Pro. The metal-binding residues are located in a single subunit, but the residues surrounding the active site are contributed by three subunits. The fold of the protein resembles that of creatine amidinohydrolase (creatinase, not a metalloenzyme). The C-terminal catalytic domain is also similar to the single-domain enzyme methionine aminopeptidase that has a dinuclear cobalt center.

 

== References ==

[[Category: Xaa-Pro aminopeptidase]]

[[Category: Bond, C S]]

[[Category: Dixon, N E]]

[[Category: Freeman, H C]]

[[Category: Guss, J M]]

[[Category: Lilley, P E]]

[[Category: Wilce, M C]]

[[Category: Proline peptidase-dipeptide inhibitor complex]]