Maintenance of the monomeric structure of glucokinase under reacting conditions
Author
dc.contributor.author
Cárdenas, María Luz
Author
dc.contributor.author
Rabajille, Eliana
Author
dc.contributor.author
Niemeyer, Hermann
Admission date
dc.date.accessioned
2018-12-20T14:08:11Z
Available date
dc.date.available
2018-12-20T14:08:11Z
Publication date
dc.date.issued
1978
Cita de ítem
dc.identifier.citation
Archives of Biochemistry and Biophysics, Volumen 190, Issue 1, 2018, Pages 142-148
Identifier
dc.identifier.issn
10960384
Identifier
dc.identifier.issn
00039861
Identifier
dc.identifier.other
10.1016/0003-9861(78)90261-8
Identifier
dc.identifier.uri
https://repositorio.uchile.cl/handle/2250/154128
Abstract
dc.description.abstract
Glucokinase is a monomeric protein under native and denaturating conditions yet presents a sigmoidal saturation function for glucose. These peculiarities suggested the possibility that polymerization occurs under assay conditions. Thus the apparent molecular weight of glucokinase was determined by gel filtration at 4 °C and at 30 °C in the presence of substrates and products, singly and in combination, creating during the filtration similar conditions as used in the assay. Gel filtration was performed also in the presence of N-acetylglucosamine, which is a competitive inhibitor and shifts to an hyperbole the saturation function for glucose. The same elution behavior, that is, a single symmetrical peak, was observed in every system used. This persistent monomeric form of glucokinase excludes the possibility that the sigmoidal function is the result of the interaction of different subunits. The possibility of an association-dissociation equilibrium in which the kinetic properties of the