Identifying how the chemical subsystems of metabolism have changed

February 25, 2014

To better understand the emergence of life, former SFI Omidyar Fellow Rogier Braakman and External Professor Eric Smith are taking a careful look at Aquifex aeolicus.

Being restricted to extreme, boiling hot spring habitats (a consistent feature of Earth's geology) means the unusual bacterium's metabolic network has evolved less than those of other species. This makes it a great model system to study the early of metabolism, the researchers say.

The pair is using a technique called phylometabolic analysis, which combines the building of gene-based family trees of relatedness (called phylogenies) with reconstruction of chemical metabolic networks. This lets the researchers "see not just what information is changing, but how specific driving forces are changing the underlying chemical networks encoded by those genes," explains Braakman.

Their research, published February 5 in PLOS ONE, highlights three main drivers of evolution: optimizing kinetics, either by replacing generalist enzymes with multiple, specialized enzymes or by fusing successive enzymes in a pathway together to minimize diffusion; and optimizing thermodynamics by choosing pathways that use less energy. These drivers, they say, evoke a major tradeoff in evolution – speed versus efficiency – and suggest that early ancestors probably started with a smaller assortment of enzymes, each of which could weakly catalyze many different reactions.

By identifying how the chemical subsystems of metabolism have changed, researchers might infer phenotypic features of the universal common ancestor, notes Braakman, and even link the competition for resources across different branches of the tree of life to the evolution of the major elemental cycles in the biosphere.

Explore further: Finding the roots and early branches of the tree of life

More information: Braakman R, Smith E (2014) "Metabolic Evolution of a Deep-Branching Hyperthermophilic Chemoautotrophic Bacterium." PLoS ONE 9(2): e87950. DOI: 10.1371/journal.pone.0087950

Related Stories

Finding the roots and early branches of the tree of life

April 19, 2012

A study published in PLoS Computational Biology maps the development of life-sustaining chemistry to the history of early life. Researchers Rogier Braakman and Eric Smith of the Santa Fe Institute traced the six methods of ...

'Promiscuous' enzymes still prevalent in metabolism

August 30, 2012

Open an undergraduate biochemistry textbook and you will learn that enzymes are highly efficient and specific in catalyzing chemical reactions in living organisms, and that they evolved to this state from their "sloppy" and ...

Recommended for you

Most EU nations seek to bar GM crops

October 4, 2015

Nineteen of the 28 EU member states have applied to keep genetically modified crops out of all or part of their territory, the bloc's executive arm said Sunday, the deadline for opting out of new European legislation on GM ...

Ancestral background can be determined by fingerprints

September 28, 2015

A proof-of-concept study finds that it is possible to identify an individual's ancestral background based on his or her fingerprint characteristics – a discovery with significant applications for law enforcement and anthropological ...

Trade in invasive plants is blossoming

October 3, 2015

Every day, hundreds of different plant species—many of them listed as invasive—are traded online worldwide on auction platforms. This exacerbates the problem of uncontrollable biological invasions.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.