Dissecting the functional roles of the conserved NXXE and HXE motifs of the ADP-dependent glucokinase from Thermococcus litoralis
Author
dc.contributor.author
Abarca Lagunas, María José
Author
dc.contributor.author
Rivas Pardo, Jaime
Author
dc.contributor.author
Ramírez Sarmiento, César
Author
dc.contributor.author
Giuxé Leguia, Victoria
Admission date
dc.date.accessioned
2015-12-30T01:37:20Z
Available date
dc.date.available
2015-12-30T01:37:20Z
Publication date
dc.date.issued
2015
Cita de ítem
dc.identifier.citation
FEBS Letters 589 (2015) 3271–3276
en_US
Identifier
dc.identifier.issn
0014-5793
Identifier
dc.identifier.other
DOI: 10.1016/j.febslet.2015.09.013
Identifier
dc.identifier.uri
https://repositorio.uchile.cl/handle/2250/136060
General note
dc.description
Artículo de publicación ISI
en_US
Abstract
dc.description.abstract
The activity of the ADP-dependent glucokinase from Thermococcus litoralis (TlGK) relies on the
highly conserved motifs NXXE (i.e. Asn-Xaa-Xaa-Glu) and HXE (i.e. His-Xaa-Glu). Site-directed mutagenesis
of residues Glu279 (HXE) and Glu308 (NXXE) leads to enzymes with highly reduced catalytic
rates. The replacement of Glu308 by Gln increased the KM for MgADP and was activated by free
Mg2+. On the other hand, HXE mutants did not affect the KM for MgADP , were still inhibited by free
Mg2+, and caused a large increase on KM for glucose and an 87-fold weaker binding of glucose onto
the non-hydrolysable TlGK AMP–AlF3 complex. Our findings put forward the fundamental role of
the HXE motif in glucose binding during ternary complex formation
en_US
Patrocinador
dc.description.sponsorship
Fondo Nacional de Desarrollo Cientifico y Tecnologico (FONDECYT), Chile
1110137
1150460