The invention includes a database of candidate essential genes in Pseudomonas aeruginosa, as well as other important genes that, when mutated, lead to a growth attenuated phenotype. Such genes and mutants of such genes are important for identifying antibacterial agents suitable for treating and preventing Pseudomonas aeruginosa infections. The invention includes methods for confirming the essentiality or importance of candidate genes, as well as methods for utilizing those genes to screen for new antibacterial drugs. The invention also includes the antibacterial agents identified using the disclosed methods, as well as methods of using the same for treating and preventing Pseudomonas infection.