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The Regulation of Cellular Systems

TLDR
The basic equations of metabolic control analysis are rewritten in terms of co-response coefficients and internal response coefficients to describe the interaction of optimization methods and the interrelation with evolution.
Abstract
Introduction Fundamentals of biochemical modeling Balance equations Rate laws Generalized mass-action kinetics Various enzyme kinetic rate laws Thermodynamic flow-force relationships Power-law approximation Steady states of biochemical networks General considerations Stable and unstable steady states Multiple steady states Metabolic oscillations Background Mathematical conditions for oscillations Glycolytic oscillations Models of intracellular calcium oscillations A simple three-variable model with only monomolecular and bimolecular reactions Possible physiological significance of oscillations Stoichiometric analysis Conservation relations Linear dependencies between the rows of the stoichiometry matrix Non-negative flux vectors Elementary flux modes Thermodynamic aspects A generalized Wegscheider condition Strictly detailed balanced subnetworks Onsager's reciprocity reactions for coupled enyme reactions Time hierarchy in metabolism Time constants The quasi-steady-state approximation The Rapid equilibrium approximation Modal analysis Metabolic control analysis Basic definitions A systematic approach Theorems of metabolic control analysis Summation theorems Connectivity theorems Calculation of control coefficients using the theorems Geometrical interpretation Control analysis of various systems General remarks Elasticity coefficients for specific rate laws Control coefficients for simple hypothetical pathways Unbranched chains A branched system Control of erythrocyte energy metabolism The reaction system Basic model Interplay of ATP production and ATP consumption Glycolytic energy metabolism and osmotic states A simple model of oxidative phosphorylation A three-step model of serine biosynthesis Time-dependent control coefficients Are control coefficients always parameter independent? Posing the problem A system without conserved moieties A system with a conserved moiety A system including dynamic channeling Normalized versus non-normalized coefficients Analysis in terms of variables other than steady-state concentrations and fluxes General analysis Concentration ratios and free-energy-differences as state variables Entropy production as response variable Control of transient times Control of oscillations A second-order approach A quantitative approach to metabolic regulations Co-response coefficients Fluctuations of internal variables versus parameter perturbations Internal response coefficients Rephrasing the basic equations of metabolic control analysis in terms of co-response coefficients and internal response coefficients Control within and between subsystems Modular approach Overall elasticities Overall control coefficients Flux control insusceptibility Control exerted by elementary steps in enzyme catalysis Control analysis of metabolic channeling Comparison of metabolic control analysis and power-law formalism Computational aspects Application of optimization methods and the interrelation with evolution Optimization of the catalytic properties of single enzymes Basic assumptions Optimal values of elementary rate constants Optimal Michaelis constants Optimization of multienzyme systems Maximization of steady-state flux Influence of osmotic constraints and minimization of intermediate concentrations Minimization of transient times Optimal stoichiometries.

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The geometry of biological time , by A. T. Winfree. Pp 544. DM68. Corrected Second Printing 1990. ISBN 3-540-52528-9 (Springer)

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Modeling and simulation of genetic regulatory systems: a literature review.

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COPASI---a COmplex PAthway SImulator

TL;DR: COPASI is presented, a platform-independent and user-friendly biochemical simulator that offers several unique features, and numerical issues with these features are discussed; in particular, the criteria to switch between stochastic and deterministic simulation methods, hybrid deterministic-stochastic methods, and the importance of random number generator numerical resolution in Stochastic simulation.
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Complete nitrification by Nitrospira bacteria

TL;DR: The discovery and cultivation of a completely nitrifying bacterium from the genus Nitrospira, a globally distributed group of nitrite oxidizers, and the genome of this chemolithoautotrophic organism encodes the pathways both for ammonia and nitrite oxidation.
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Analysis of optimality in natural and perturbed metabolic networks

TL;DR: The method of minimization of metabolic adjustment (MOMA), whereby the hypothesis that knockout metabolic fluxes undergo a minimal redistribution with respect to the flux configuration of the wild type is tested, is tested and found to be useful in understanding the evolutionary optimization of metabolism.
References
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Dynamic stability of steady states and static stabilization in unbranched metabolic pathways

TL;DR: Sufficient and necessary conditions for asymptotic stability of the steady state in the general case of the pathway with a single feedback loop have been established and the range of dynamic stability can be widened greatly, if the pathway contains one or two reactions of relatively small effective rate constants.
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'Channelled' pathways can be more sensitive to specific regulatory signals.

TL;DR: It is shown that in the response of ‘channelled’ pathways to an external signal, additional terms appear that reflect the direct enzyme‐enzyme interactions and tend to enhance the responsiveness of the pathway.
Book ChapterDOI

Metabolic Control Analysis in Theory and Practice

TL;DR: Instead of assuming the existence of “key enzymes,” metabolic control analysis allows the contribution of each enzyme to be quantified, which allows the classical ideas of metabolic regulation to be placed on a more secure theoretical base.
Journal ArticleDOI

In vitro demonstration of alternate stationary states in an open enzyme system containing phosphofructokinase

TL;DR: The kinetic properties of an open reconstituted enzyme system are investigated with the aim of demonstrating experimentally hysteretic transitions between alternate stationary states and the existence of multiple stationary states is shown experimentally within precisely definable parameters.
Journal ArticleDOI

Mathematical modelling of dynamics and control in metabolic networks. III. Linear reaction sequences

TL;DR: Kinetics of linear sequences of enzymatic reactions converting a single substrate into a single product are examined with emphasis on obtaining the relationship between the individual kinetic parameters and overall dynamic behavior.