Scale-rich metabolic networks: background and introduction

TL;DR

This paper explores the complex, scale-rich modular architecture of biological metabolic networks, highlighting their organized structure, variability, and robustness, supported by empirical bacterial data and a simplified model.

Contribution

It introduces the concept of scale-rich, self-dissimilar modularity in metabolic networks and demonstrates these features through bacterial data and a basic abstract model.

Findings

Metabolic networks exhibit scale-rich, modular, and self-dissimilar structures.

Degree distributions follow power-law behaviors.

Networks show high variability and organized robustness.

Abstract

Recent progress has clarified many features of the global architecture of biological metabolic networks, which have highly organized and optimized tolerances and tradeoffs (HOT) for functional requirements of flexibility, efficiency, robustness, and evolvability, with constraints on conservation of energy, redox, and many small moieties. One consequence of this architecture is a highly structured modularity that is self-dissimilar and scale-rich, with extremes in low and high variability, including power laws, in both metabolite and reaction degree distributions. This paper illustrates these features using the well-understood stoichiometry of metabolic networks in bacteria, and a simple model of an abstract metabolism.