Excess Mutual Catalysis Is Required for Effective Evolvability

@article{Markovitch2012ExcessMC,
  title={Excess Mutual Catalysis Is Required for Effective Evolvability},
  author={Omer Markovitch and Doron Lancet},
  journal={Artificial Life},
  year={2012},
  volume={18},
  pages={243-266}
}
It is widely accepted that autocatalysis constitutes a crucial facet of effective replication and evolution (e.g., in Eigen's hypercycle model). Other models for early evolution (e.g., by Dyson, Gánti, Varela, and Kauffman) invoke catalytic networks, where cross-catalysis is more apparent. A key question is how the balance between auto- (self-) and cross- (mutual) catalysis shapes the behavior of model evolving systems. This is investigated using the graded autocatalysis replication domain… 
Mathematical Analysis of a Prototypical Autocatalytic Reaction Network
TLDR
It is shown that when quasi-steady-state approximation is applicable for at least one of the components, the deviation from the exponential growth is small and the presence of a substantial noncatalytic conversion of substrates will create broad regions where autocatalysts can coexist.
How Catalytic Order Drives the Complexification of Molecular Replication Networks
Catalytic replication networks have frequently served to study emergent phenomena in complex mixtures. In a series of recent research papers, we have analyzed the effects of the autocatalytic
Predicting species emergence in simulated complex pre-biotic networks
TLDR
The following hypothesis is explored: when replaying the tape, the details of the outcomes would vary but certain “invariants” might emerge across different life-tapes sharing similar initial conditions, and large-scale simulations of an in silico model of pre-biotic evolution called GARD are used to test this hypothesis.
Autocatalytic Networks at the Basis of Life’s Origin and Organization
TLDR
The suggestion that simple inorganic molecules like metals and minerals may have been the earliest catalysts in the formation of prebiotic autocatalytic sets is elaborated, and how RAF theory may also be applied to systems beyond chemistry, such as ecology, economics, and cognition.
Prebiotic network evolution: six key parameters.
TLDR
The origins of life likely required the cooperation among a set of molecular species interacting in a network, and six parameters emerge as the most influential when one considers the molecular characteristics of the best candidates for the emergence of biological information: polypeptides, RNA-like polymers, and lipids.
Prebiotic Evolution of Molecular Assemblies: From Molecules to Ecology
TLDR
A prebiotic model that allows one to relate parameters of chemical interaction networks within molecular assemblies to emergent ecological and evolutionary properties in populations of such assemblies is explored, finding that compotypes with a larger intrinsic molecular repertoire show a higher intrinsic growth and lower carrying capacity, as well as lower replication fidelity.
Population Dynamics of Autocatalytic Sets in a Compartmentalized Spatial World
TLDR
A recently developed software tool is used to simulate exactly this scenario of the emergence and dynamics of autocatalytic sets in populations of compartments in a spatial environment, as an important first step towards more realistic simulations and experiments on autoc atalytic set in protocells.
Erratum to: An Experimental Framework for Generating Evolvable Chemical Systems in the Laboratory
TLDR
This work proposes high-throughput screening of a diverse set of conditions in order to identify combinations of Bfood,^ energy sources, and mineral surfaces that foster the emergence of surface-associated chemical consortia that are capable of adaptive evolution.
Heredity in Messy Chemistries
TLDR
It is shown that by linearising around a fixed point in a chemical reaction network and solving the corresponding eigenvalue problem, it is possible to detect the set of independent autocatalytic subnetworks that can operate in the vicinity of that point.
...
...

References

SHOWING 1-10 OF 71 REFERENCES
Mutations and Lethality in Simulated Prebiotic Networks
TLDR
The analyses presented help establish GARD as a workable alternative prebiotic scenario, suggesting that life may have begun with large molecular networks of low fidelity, that later underwent evolutionary compaction and fidelity augmentation.
Emergence of symbiosis in peptide self-replication through a hypercyclic network
TLDR
A chemical system is reported that constitutes a clear example of a minimal hypercyclic network, in which two otherwise competitive self-replicating peptides symbiotically catalyse each others' production.
Lack of evolvability in self-sustaining autocatalytic networks constraints metabolism-first scenarios for the origin of life
TLDR
It is demonstrated here that replication of compositional information is so inaccurate that fitter compositional genomes cannot be maintained by selection and the system lacks evolvability, cautions against metabolism-first theories of the origin of life, although ancient metabolic systems could have provided a stable habitat within which polymer replicators later evolved.
The hypercycle. A principle of natural self-organization. Part A: Emergence of the hypercycle.
TLDR
An analysis of experimental data regarding RNA and D N A replication reveals that a sufficient amount of information for the build up of a translation machinery can be gained only via integration of several different replicative units (or reproductive cycles) throughfimctional linkages.
Coevolution of compositional protocells and their environment
TLDR
The EE-GARD model is the first GARD model to portray a possible time evolution of the composomes repertoire, and is suggested that similar processes can take place before the onset of life, where protocellular entities, rather than full-fledged living systems, coevolve along with their surroundings.
The molecular roots of compositional inheritance.
TLDR
It is demonstrated that the fidelity of reproduction provided by a newly defined heritability measure eta(*)(s), strongly depends on the values of molecular recognition parameters and on assembly size, where N(G)is the size of the primordial molecular repertoire and lambda is a molecular interaction statistical parameter.
Kinetic Origin of Heredity in a Replicating System with a Catalytic Network
  • K. Kaneko
  • Biology
    Journal of biological physics
  • 2002
TLDR
It is shown that evolvability is realized in the itinerancy phase, where a change in the number of minority molecules controls a change of the chemical state.
From replicators to reproducers: the first major transitions leading to life.
TLDR
Griesemer's concept of a reproducer is outlined, which brings out the essential role of development in evolution, and it is suggested that this binding originated, not as a step in protein synthesis, but in the formation of coenzymes in a metabolically complex RNA world.
Compositional complementarity and prebiotic ecology in the origin of life
TLDR
It is hypothesized that life began not with the first self‐reproducing molecule or metabolic network, but as a prebiotic ecology of co‐evolving populations of macromolecular aggregates (composomes) that varied in properties and functions such as stability, catalysis, fission, fusion and selective accumulation of molecules from solution.
Polymer Gard: Computer Simulation of Covalent Bond Formation in Reproducing Molecular Assemblies
TLDR
The P-GARD model offers a scenario whereby biopolymer formation may be a result of rather than a prerequisite for early life-like processes, and is tested with computer simulations of a simple case of monovalent monomers, whereby more complex molecules are formed internally, in a manner resembling biosynthetic metabolism.
...
...