Inverse Relationship Between Molecular Diversity And Resource Abundances

TL;DR

This study explains why cellular molecular diversity increases as environmental resources become scarce, showing a tradeoff between resource utility and reaction efficiency that sustains diversity.

Contribution

It introduces a cell model demonstrating how resource limitation promotes molecular diversity through a growth optimization tradeoff.

Findings

Molecular diversity increases as resource abundance decreases.

Diversity scales with a negative power of resource levels.

Tradeoff between resource utility and reaction rate explains diversity dynamics.

Abstract

Cell reproduction involves replication of diverse molecule species, in contrast to simple replication system with fewer components. Here, we address why such diversity is sustained despite the efficiency of simple replication systems, using a cell model with catalytic reaction dynamics that grew by uptake of environmental resources. Limited resources led to increased diversity of components within the system, and the number of coexisting species increased with a negative power of the resource abundances. The diversity was explained from the optimum growth speed of the cell, determined by a tradeoff between the utility of diverse resources and the concentration onto fewer components to increase the reaction rate.