Recent application of metagenomic approaches toward the discovery of antimicrobials and other bioactive small molecules

Bacteria grown in pure culture have been the starting point for the discovery of many of the antibacterials now in use. Metagenomics, which utilizes culture-independent methods to access the collective genomes of natural bacterial populations, provides a means of exploring the antimicrobials produced by the large collections of bacteria that are known to be present in the environment but remain recalcitrant to culturing. Both novel small molecule antibiotics and new antibacterially active proteins have been identified using metagenomic approaches. The recent application of metagenomics to the discovery of bioactive small molecules, small molecule biosynthetic gene clusters and antibacterially active enzymes is discussed here.