Whole genome scan for habitat-specific genes by signature-tagged mutagenesis.

Large numbers of new open reading frames can be identified by whole genome sequencing of microbial genomes. Efficient new approaches are required to investigate the role of the putative genes, or to identify genes required in distinct habitats. The novel technique 'signature-tagged mutagenesis' allows the identification of individual mutants within complex pools of mutants. Large numbers of mutants can be analyzed in a parallel manner for negative phenotypes like loss of function or attenuation of virulence. Further analysis of mutations identified by a negative selection procedure can be performed by linking the position of the respective mutations to genes identified by whole genome sequencing of microbes.