Structure and catalytic mechanism of glucosamine 6-phosphate deaminase from Escherichia coli at 2.1 Å resolution
MetadataShow full item record
Background: Glucosamine 6-phosphate deaminase from Escherichia coli is an allosteric hexameric enzyme which catalyzes the reversible conversion of D-glucosamine 6-phosphate into D-fructose 6-phosphate and ammonium ion and is activated by N-acetyl-D-glucosamine 6-phosphate. Mechanistically, it belongs to the group of aldose-ketose isomerases, but its reaction also accomplishes a simultaneous amination/deamination. The determination of the structure of this protein provides fundamental knowledge for understanding its mode of action and the nature of allosteric conformational changes that regulate its function. Results: The crystal structure of glucosamine 6-phosphate deaminase with bound phosphate ions is presented at 2.1 Å resolution together with the refined structures of the enzyme in complexes with its allosteric activator and with a competitive inhibitor. The protein fold can be described as a modified NAD-binding domain. Conclusions: From the similarities between the three presented structures, it is concluded that these represent the enzymatically active R state conformer. A mechanism for the deaminase reaction is proposed. It comprises steps to open the pyranose ring of the substrate and a sequence of general base-catalyzed reactions to bring about isomerization and deamination, with Asp72 playing a key role as a proton exchanger.
How to cite this document
Showing items related by title, author, creator and subject.
Saska, S. ; Nunes, N. S. ; Aveiro, E. ; Pavan, C. A C ; Santagneli, S. H. ; Campos, J. A D B ; Gaspar, A. M M ; Ribeiro, Sidney José Lima ; Messaddeq, Younes (Key Engineering Materials, 2009) [Artigo]Bioceramics with different Ca/P ratio were prepared from a mechanical mixture of NaPO3, CaCO3, Ca(OH)2 and phosphate buffer solution and implanted in rats subcutaneous tissues. The cements were characterized by Thermo ...
He, Wenxiao; Andersson, Martin; Souza, Pedro Paulo Chaves de ; De Souza Costa, Carlos Alberto ; Muñoz, Eduardo Mariscal ; Schwartz-Filho, Humberto Osvaldo ; Hayashi, Mariko; Hemdal, Amanda; Fredel, Axel; Wennerberg, Ann et al. (Biomedical Materials (Bristol), 2013) [Artigo]This study investigated the effects of the morphology and physicochemical properties of calcium phosphate (CaP) nanoparticles on osteogenesis. Two types of CaP nanoparticles were compared, namely amorphous calcium phosphate ...
Minarelli-Gaspar, A. M. ; Zavaglia, C. A C; Saska, S. ; Jimenez, J.; Da Cunha, L. R. ; Bolini, Paulo Domingos André ; Leal, C.; Morejón-Alonso, L.; Carrodeguas, R. G.; López-Bravo, A. (Key Engineering Materials, 2008) [Trabalho apresentado em evento]The biological behavior of a new bioactive material composed of calcium-deficient hydroxyapatite, octacalcium phosphate, and β-tricalcium phosphate was investigated by in vitro indirect and direct cytotoxicity, cell adhesion ...