A recent study by researchers at the University of Hawaii – Manoa (UHM) and the Oregon State University (OSU) provides strong evidence that mitochondria share a common evolutionary ancestor with a lineage of marine bacteria known as SAR11, arguably the most abundant group of microorganisms on Earth.
This is an electron micrograph of SAR11 strain HIMB4 cultured from Kaneohe Bay, Oahu, Hawaii. Credit: Michael Rappe, SOEST/UHM
"This is a very exciting discovery," says Michael Rappe, Associate Researcher at the Hawaii Institute of Marine Biology in the School of Ocean and Earth Science and Technology (SOEST) at UHM. "The results that we present make sense in a lot of ways: the physiology of SAR11 makes them more apt to be dependent on other organisms, and based on the contemporary abundance of SAR11 in the global ocean, the ancestral lineage may have also been abundant in the ancient ocean, increasing encounters between this bacterial lineage with the host of the original symbiosis event."
In order to understand the evolutionary history of the SAR11 clade of marine bacteria, colleagues at Oregon State University compared the genomics of mitochondria from diverse supergroups of eukaryotes (including Excavata, Chromalveolata, and Archaeplastida) with the genomics of SAR11 strains isolated by Rappe's laboratory using several interconnected computer programs. This approach provided highly sophisticated and thorough phylogenetic analysis of these genomes. In addition to discovering the evolutionary connection between mitochondria and SAR11, the phylogenomics-based assessment of the diversity of this group (i.e. an assessment based on the entire genome, rather than single genes) provided substantial support for proposing a new family of bacteria, Pelagibacteraceae, fam. nov. "The implication is that the lineage of highly abundant marine bacteria known as SAR11 contains a significant amount of genetic diversity, which potentially indicates significant diversity in metabolism," notes Rappe.
Rappe and colleagues at SOEST and OSU continue to grow new strains of SAR11 and probe their genomes to further understand their metabolic potential and how they have become so successful in the global ocean.
Nature Scientific Reports: Phylogenomic evidence for a common ancestor of mitochondria and the SAR11 clade, DOI:10.1038/srep00013
Marcie Grabowski | EurekAlert!
Cells communicate in a dynamic code
19.02.2018 | California Institute of Technology
Studying mitosis' structure to understand the inside of cancer cells
19.02.2018 | Biophysical Society
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