Homestake gold mineWIKIPEDIA, RACHEL HARRISThe tree of life is dominated by microbes, but many large branches remain uncharted because scientists have been historically restricted to studying the small fraction of species that will grow in a lab. An international team of scientists has now begun to redress this bias, sequencing full genomes from single cells to bring the “uncultured majority” into view.
In total, the team identified more than 200 new microbial species belonging to 29 underrepresented or unknown lineages. And the results, published today (July 14) in Nature, were full of new metabolic abilities and genetic surprises.
“[There has been a] strong imperative to fill in the microbial tree of life,” said Philip Hugenholtz from the University of Queensland, one of the study’s leaders. “If you have an incomplete view of evolution—vastly incomplete in the case of microorganisms—you have a vastly incomplete understanding of biology.”
By sequencing DNA directly from environmental samples, geneticists have suggested that the two microbial domains of life—bacteria and archaea—include at least 60 major lineages (phyla), but just four of these account for more than 88 percent of cultivated microbes. Of the ...
