Escalation of error catastrophe for enzymatic self-replicators

TL;DR

This paper investigates how enzymatic self-replication affects error thresholds in origin-of-life models, revealing a lower error tolerance due to frequency-dependent replication rates, with implications for catalytic network stability.

Contribution

It extends quasispecies models to enzymatic replication with recognition regions, showing a reduced error threshold and analyzing hypercyclic catalytic networks.

Findings

Error threshold is significantly lowered in enzymatic self-replicators.

Replication rate decreases as the fraction of functional enzymes increases.

Hypercyclic networks exhibit similar error catastrophe behavior.

Abstract

It is a long-standing question in origin-of-life research whether the information content of replicating molecules can be maintained in the presence of replication errors. Extending standard quasispecies models of non-enzymatic replication, we analyze highly specific enzymatic self-replication mediated through an otherwise neutral recognition region, which leads to frequency-dependent replication rates. We find a significant reduction of the maximally tolerable error rate, because the replication rate of the fittest molecules decreases with the fraction of functional enzymes. Our analysis is extended to hypercyclic couplings as an example for catalytic networks.