Description of Chemical Systems by means of Response Functions

TL;DR

This paper introduces a formalism using renewal equations to describe biochemical system responses, linking linear ODE interactions to renewal models, with applications to biological systems and analysis of long-term behavior.

Contribution

It develops a novel formalism connecting linear ODE models of biochemical systems with renewal equations, including properties of kernels under detailed balance.

Findings

Renewal equations can represent interactions in biochemical systems.

Kernels satisfy complete monotonicity under detailed balance.

Long-term behavior of solutions analyzed.

Abstract

In this paper we introduce a formalism that allows to describe the response of a part of a biochemical system in terms of renewal equations. In particular, we examine under which conditions the interactions between the different parts of a chemical system, described by means of linear ODEs, can be represented in terms of renewal equations. We show also how to apply the formalism developed in this paper to some particular types of linear and non-linear ODEs, modelling some biochemical systems of interest in biology (for instance, some time-dependent versions of the classical Hopfield model of kinetic proofreading). We also analyse some of the properties of the renewal equations that we are interested in, as the long-time behaviour of their solution. Furthermore, we prove that the kernels characterising the renewal equations derived by biochemical system with reactions that satisfy the detail balance condition belong to the class of completely monotone functions.