Paper Info
Title
Model and simulation of Na+/K+ pump phosphorylation in the presence of palytoxin
Abstract
The ATP hydrolysis reactions responsible for the Na^+/K^+-ATPase phosphorylation, according to recent experimental evidences, also occur for the PTX-Na^+/K^+ pump complex. Moreover, it has been demonstrated that PTX interferes with the enzymes phosphorylation status. However, the reactions involved in the PTX-Na^+/K^+ pump complex phosphorylation are not very well established yet. This work aims at proposing a reaction model for PTX-Na^+/K^+ pump complex, with similar structure to the Albers-Post model, to contribute to elucidate the PTX effect over Na^+/K^+-ATPase phosphorylation and dephosphorylation. Computational simulations with the proposed model support several hypotheses and also suggest: (i) phosphorylation promotes an increase of the open probability of induced channels; (ii) PTX reduces the Na^+/K^+ pump phosphorylation rate; (iii) PTX may cause conformational changes to substates where the Na^+/K^+-ATPase may not be phosphorylated; (iv) PTX can bind to substates of the two principal states E1 and E2, with highest affinity to phosphorylated enzymes and with ATP bound to its low-affinity sites. The proposed model also allows previewing the behavior of the PTX-pump complex substates for different levels of intracellular ATP concentrations.
Year
DOI
Venue
2008
10.1016/j.compbiolchem.2007.08.001
Computational Biology and Chemistry
Keywords
Field
DocType
enzyme,computer simulation,modeling and simulation,phosphorylation,na k atpase
Palytoxin,Computational simulation,Phosphorylation,Enzyme,ATP hydrolysis,Dephosphorylation,Na+/K+-ATPase,Intracellular,Chemistry,Stereochemistry
Journal
Volume
Issue
ISSN
32
1
1476-9271
Citations 
PageRank 
References 
6
0.94
0
Authors
5
Name
Order
Citations
PageRank
Antônio M. Rodrigues181.79
Antônio-Carlos G. Almeida282.13
Antonio F.C. Infantosi381.79
Hewerson Z. Teixeira482.13
Mário A. Duarte560.94