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1zli
From Proteopedia
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| , resolution 2.09Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | |||||||
| Activity: | Carboxypeptidase B, with EC number 3.4.17.2 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal structure of the tick carboxypeptidase inhibitor in complex with human carboxypeptidase B
Overview
The tick carboxypeptidase inhibitor (TCI) is a proteinaceous inhibitor of metallo-carboxypeptidases present in the blood-sucking tick Rhipicephalus bursa. The three-dimensional crystal structures of recombinant TCI bound to bovine carboxypeptidase A and to human carboxypeptidase B have been determined and refined at 1.7 A and at 2.0 A resolution, respectively. TCI consists of two domains that are structurally similar despite the low degree of sequence homology. The domains, each consisting of a short alpha-helix followed by a small twisted antiparallel beta-sheet, show a high level of structural homology to proteins of the beta-defensin-fold family. TCI anchors to the surface of mammalian carboxypeptidases in a double-headed manner not previously seen for carboxypeptidase inhibitors: the last three carboxy-terminal amino acid residues interact with the active site of the enzyme in a way that mimics substrate binding, and the N-terminal domain binds to an exosite distinct from the active-site groove. The structures of these complexes should prove valuable in the applications of TCI as a thrombolytic drug and as a basis for the design of novel bivalent carboxypeptidase inhibitors.
About this Structure
1ZLI is a Protein complex structure of sequences from Homo sapiens and Rhipicephalus bursa. Full crystallographic information is available from OCA.
Reference
The three-dimensional structures of tick carboxypeptidase inhibitor in complex with A/B carboxypeptidases reveal a novel double-headed binding mode., Arolas JL, Popowicz GM, Lorenzo J, Sommerhoff CP, Huber R, Aviles FX, Holak TA, J Mol Biol. 2005 Jul 15;350(3):489-98. PMID:15961103
Page seeded by OCA on Thu Mar 20 15:36:59 2008
Categories: Carboxypeptidase B | Homo sapiens | Protein complex | Rhipicephalus bursa | Arolas, J L. | Aviles, F X. | Holak, T A. | Huber, R. | Lorenzo, J. | Popowicz, G M. | Sommerhoff, C P. | ZN | Beta-defensin fold (tci) | Eight-stranded twisted beta-sheet surrounded by eight alpha-helices (cpb) | Inhibitor-metallocarboxypeptidase complex
