Using genomic microarrays to study insertional/transposon mutant libraries.

The rapid expanse of microbial genome databases provides incentive and opportunity to study organismal behavior at the whole-genome level. While many newly sequenced genes are assigned names based on homology to previously characterized genes, many putative open reading frames remain to be annotated. The use of microarrays enables functional characterization of the entire genome with respect to genes important for different growth conditions including nutrient deprivation, stress responses, and virulence. The methods described here combine advancements in the identification of genomic sequences flanking insertional mutants with microarray methodology. The combination of these methods facilitates tracking large numbers of mutants for phenotypic studies. This improves both the efficiency of genome-saturating library screens and contributes to the functional annotation of unknown genes.