Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/79627
Type: Artigo de periódico
Title: Structural analysis of N-acetylglucosamine-6-phosphate deacetylase apoenzyme from Escherichia coli
Author: Ferreira, FM
Mendoza-Hernandez, G
Castaneda-Bueno, M
Aparicio, R
Fischer, H
Calcagno, ML
Oliva, G
Abstract: 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 angstrom) iodine anomalous scattering and it was refined against a native dataset up to 2.0 angstrom 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. (c) 2006 Elsevier Ltd. All rights reserved.
Subject: N-acetylglucosamine-6-phosphate deacetylase
amino sugar catabolism
amidohydrolases
PIXE
ICP-AES
Country: Inglaterra
Editor: Academic Press Ltd Elsevier Science Ltd
Rights: fechado
Identifier DOI: 10.1016/j.jmb.2006.03.024
Date Issue: 2006
Appears in Collections:Unicamp - Artigos e Outros Documentos

Files in This Item:
File Description SizeFormat 
WOS000237908700006.pdf879.24 kBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.