1yrr
From Proteopedia
| |||||||
| , resolution 2.00Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||
| Gene: | nagA (Escherichia coli) | ||||||
| Activity: | N-acetylglucosamine-6-phosphate deacetylase, with EC number 3.5.1.25 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal Structure Of The N-Acetylglucosamine-6-Phosphate Deacetylase From Escherichia Coli K12 at 2.0 A Resolution
Overview
We report the crystal structure of the apoenzyme of N-acetylglucosamine-6-phosphate (GlcNAc6P) deacetylase from Escherichia coli (EcNAGPase) and the spectrometric evidence of the presence of Zn2+ in the native protein. The GlcNAc6P deacetylase is an enzyme of the amino sugar catabolic pathway that catalyzes the conversion of the GlcNAc6P into glucosamine 6-phosphate (GlcN6P). The crystal structure was phased by the single isomorphous replacement with anomalous scattering (SIRAS) method using low-resolution (2.9 A) iodine anomalous scattering and it was refined against a native dataset up to 2.0 A resolution. The structure is similar to two other NAGPases whose structures are known from Thermotoga maritima (TmNAGPase) and Bacillus subtilis (BsNAGPase); however, it shows a phosphate ion bound at the metal-binding site. Compared to these previous structures, the apoenzyme shows extensive conformational changes in two loops adjacent to the active site. The E. coli enzyme is a tetramer and its dimer-dimer interface was analyzed. The tetrameric structure was confirmed in solution by small-angle X-ray scattering data. Although no metal ions were detected in the present structure, experiments of photon-induced X-ray emission (PIXE) spectra and of inductively coupled plasma emission spectroscopy (ICP-AES) with enzyme that was neither exposed to chelating agents nor metal ions during purification, revealed the presence of 1.4 atoms of Zn per polypeptide chain. Enzyme inactivation by metal-sequestering agents and subsequent reactivation by the addition of several divalent cations, demonstrate the role of metal ions in EcNAGPase structure and catalysis.
About this Structure
1YRR is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Structural analysis of N-acetylglucosamine-6-phosphate deacetylase apoenzyme from Escherichia coli., Ferreira FM, Mendoza-Hernandez G, Castaneda-Bueno M, Aparicio R, Fischer H, Calcagno ML, Oliva G, J Mol Biol. 2006 Jun 2;359(2):308-21. Epub 2006 Mar 29. PMID:16630633
Page seeded by OCA on Mon Mar 31 01:19:55 2008
