Table of Contents
Journal of Biophysics
Volume 2011 (2011), Article ID 579402, 17 pages
http://dx.doi.org/10.1155/2011/579402
Research Article

EI of the Phosphotransferase System of Escherichia coli: Mathematical Modeling Approach to Analysis of Its Kinetic Properties

1Physics Department, Moscow State University, Moscow 119991, Leninskie Gory, Russia
2Institute for Systems Biology SPb, Moscow 119992, Leninskie Gory, 1/73, Russia
3School of Informatics, The University of Edinburgh, Rm 2.208, Darwin Building, Kings Buildings Edinburgh EH9 3JR, UK
4Okinawa Institute of Science and Technology 1919-1 Tancha, Onna, Okinawa 9040412, Japan
5A. N. Belozersky Institute of Physical-Chemical Biology, Moscow 119992, Leninskie Gory, Russia

Received 4 November 2010; Accepted 20 January 2011

Academic Editor: Thomas P. Burghardt

Copyright © 2011 T. A. Karelina et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The mathematical model of the operation of the first enzyme of the Escherichia coli phosphotransferase system, EI, is proposed. Parameters of the kinetic model describing the operation of EI under different conditions are identified on the basis of a large amount of known experimental data. The verified model is employed to predict modes of operation of EI under both in vivo physiological conditions and in vitro nonphysiological conditions. The model predicts that under in vivo physiological conditions, the rate of phosphotransfer from EI to the second protein of the phosphotransferase system HPr by the dimer is much higher than by the monomer. A hypothesis is proposed on the basis of calculations that the transfer by a monomer plays a role in the regulation of chemotaxis. At submicromolar pyruvate concentration, the model predicts nonmonotonic dependence of the phosphotransfer rate on the substrate (PEP) concentration.