1yrr
From Proteopedia
Crystal Structure Of The N-Acetylglucosamine-6-Phosphate Deacetylase From Escherichia Coli K12 at 2.0 A Resolution
Structural highlights
Function[NAGA_ECOLI] Catalyzes the deacetylation of N-acetyl-D-glucosamine-6-phosphate. In vitro, can also hydrolyze substrate analogs such as N-thioacetyl-D-glucosamine-6-phosphate, N-trifluoroacetyl-D-glucosamine-6-phosphate, N-acetyl-D-glucosamine-6-sulfate, N-acetyl-D-galactosamine-6-phosphate, and N-formyl-D-glucosamine-6-phosphate.[1] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedWe 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. 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[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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