1tym

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spinqualitylabelsall models 1tym, resolution 1.9Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

THE STRUCTURE OF A COMPLEX OF HEXAMERIC INSULIN AND 4'-HYDROXYACETANILIDE

Contents 1 Overview 2 Disease 3 About this Structure 4 Reference

Overview

X-ray crystallographic studies have been carried out on human insulin, crystals grown in the presence of 4'-hydroxyacetanilide (Tylenol) and show, that this nontoxic phenolic derivative can induce the T-->R transition, producing a T3R3 hexamer. Two different crystals, grown under different, conditions, are rhombohedral, space group R3, with cell constants a =, 81.11, c = 37.97 and a = 80.88, c = 37.60 A. The T3R3 hexamer is, symmetric, resulting from the presence of a crystallographic threefold, axis, and the asymmetric unit consists of a TR dimer. Data to a resolution, of 1.9 A were measured on a crystal from each of the two crystallizations, and the structures have been refined to residuals of 0.168 and 0.173. The, guest molecule is bound by the R-state monomer through the formation of, two hydrogen bonds from the hydroxy group of Tylenol to the carbonyl, oxygen and the nitrogen of A6 Cys and A11 Cys, respectively. Due to steric, constraints of the phenolic binding site, the acetamide group of Tylenol, is rotated approximately 50 degrees out of the plane of the phenyl group, and the methyl group is cis; no hydrogen bonds exist between the acetamide, group and the hexamer. Although the zinc ion, which is bound to the, R-state trimer, has tetrahedral coordination in both structures, the, T-state zinc is observed to have octahedral coordination in one structure, but tetrahedral coordination in the other. The side chain of A10 Ile in, the R-state monomer adopts a high-energy conformation as a result of close, contact to a residue in an adjacent dimer and may explain in part the, differences between therapeutic preparations of beef insulin, for which, A10 is a Val residue, and human insulin.

Disease

Known diseases associated with this structure: Diabetes mellitus, rare form OMIM:[176730], Hyperproinsulinemia, familial OMIM:[176730], MODY, one form OMIM:[176730]

About this Structure

1TYM is a Protein complex structure of sequences from Homo sapiens with ZN, CL and TYL as ligands. Full crystallographic information is available from OCA.

Reference

The structure of a complex of hexameric insulin and 4'-hydroxyacetanilide., Smith GD, Ciszak E, Proc Natl Acad Sci U S A. 1994 Sep 13;91(19):8851-5. PMID:8090735

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