2fz8

File:2fz8.jpg

spinqualitylabelsall models 2fz8, resolution 1.48Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

Human Aldose reductase complexed with inhibitor zopolrestat at 1.48 A(1 day soaking).

OverviewOverview

In structure-based drug design, accurate crystal structure determination, of protein-ligand complexes is of utmost importance in order to elucidate, the binding characteristics of a putative lead to a given target. It is, the starting point for further design hypotheses to predict novel leads, with improved properties. Often, crystal structure determination is, regarded as ultimate proof for ligand binding providing detailed insight, into the specific binding mode of the ligand to the protein. This widely, accepted practise relies on the assumption that the crystal structure of a, given protein-ligand complex is unique and independent of the protocol, applied to produce the crystals. We present two examples indicating that, this assumption is not generally given, even though the composition of the, mother liquid for crystallisation was kept unchanged: Multiple crystal, structure determinations of aldose reductase complexes obtained under, varying crystallisation protocols concerning soaking and crystallisation, exposure times were performed resulting in a total of 17 complete data, sets and ten refined crystal structures, eight in complex with zopolrestat, and two complexed with tolrestat. In the first example, a flip of a, peptide bond is observed, obviously depending on the crystallisation, protocol with respect to soaking and co-crystallisation conditions. This, peptide flip is accompanied by a rupture of an H-bond formed to the bound, ligand zopolrestat. The indicated enhanced local mobility of the complex, is in agreement with the results of molecular dynamics simulations. As a, second example, the aldose reductase-tolrestat complex is studied., Unexpectedly, two structures could be obtained: one with one, and a second, with four inhibitor molecules bound to the protein. They are located in, and near the binding pocket facilitated by crystal packing effects., Accommodation of the four ligand molecules is accompanied by pronounced, shifts concerning two helices interacting with the additional ligands.

About this StructureAbout this Structure

2FZ8 is a Single protein structure of sequence from Homo sapiens with and as ligands. Active as Aldehyde reductase, with EC number 1.1.1.21 Full crystallographic information is available from OCA.

ReferenceReference

Expect the unexpected or caveat for drug designers: multiple structure determinations using aldose reductase crystals treated under varying soaking and co-crystallisation conditions., Steuber H, Zentgraf M, Gerlach C, Sotriffer CA, Heine A, Klebe G, J Mol Biol. 2006 Oct 13;363(1):174-87. Epub 2006 Aug 9. PMID:16952371

Page seeded by OCA on Fri Feb 15 17:26:59 2008