A team of scientists led by the University of Bristol has provided new insights into the origins of the Archaea, the group of simple cellular organisms that are the ancestors of all complex life.
The Archaea are one of the Earth's most genetically and ecologically diverse groups of micro-organisms.
They thrive in a bewildering variety of habitats, from the familiar - soils and oceans - to the inhospitable and bizarre, such as the boiling acid pools of Yellowstone National Park.
The research provides a new evolutionary tree for the Archaea that will help to make sense of their biodiversity, and provides a new window into the early history of life on Earth that is not preserved in the fossil record. The work is published in PNAS.
With the development of new technologies for sequencing genomes directly from the environment, many new groups of Archaea have been discovered.
Dr Tom Williams from the School of Earth Sciences, said: "But while these genomes have greatly improved our understanding of the diversity of Archaea, they have so far failed to bring clarity to the evolutionary history of the group.
"This is because, like other micro-organisms, Archaea frequently obtain DNA from distantly related organisms by lateral gene transfer, which can greatly complicate the reconstruction of evolutionary history."
However, in their new work, Dr Williams and colleagues use a new statistical approach that combines information from thousands of genes found in many different archaeal genomes to show that events of lateral gene transfer can actually be used to orient the tree in time, resolving the deepest relationships in the evolutionary tree.
By determining which genes appeared first during the evolution of the Archaea, the new tree makes clear predictions about the basic biochemistry of the earliest Archaea, cells which may have lived over 3.5 billion years ago: these cells likely made energy using the Wood-Ljungdahl pathway, a biochemical pathway that today is found not only in Archaea but also in Bacteria, another major group of micro-organisms.
Paper: 'Integrative modelling of gene and genome evolution roots the archaeal tree of life' by T. Williams, G. Szollosi, A. Spang, T. Ettema, P. Foster, S. Heaps, T. Martin-Embley and B. Boussau in PNAS.
Shona East | EurekAlert!
Geophysicists and atmospheric scientists partner to track typhoons' seismic footprints
16.02.2018 | Princeton University
NASA finds strongest storms in weakening Tropical Cyclone Sanba
15.02.2018 | NASA/Goddard Space Flight Center
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.
But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...
Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.
The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...
Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters
Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
19.02.2018 | Materials Sciences
19.02.2018 | Materials Sciences
19.02.2018 | Life Sciences