Bacterial natural product biosynthetic diversity in geographically distinct soil microbiomes.

The number of bacterial species estimated to exist in the Earth's biosphere has increased dramatically in recent years. This newly recognized species diversity has raised the possibility that bacterial natural product diversity has also been underestimated by previous studies. Here we use comparative analysis of conserved secondary metabolite biosynthetic genes derived from three geographically distinct arid soils to show that ecologically similar microbiomes contain largely orthogonal collections of secondary metabolite biosynthetic gene sequences, suggesting that the unexplored pool of bacterial biosynthetic diversity present in nature is likely much larger than previously predicted.