<p>Diagram summarizing the results of assays of knockout mutants in nutrient uptake, human respiratory epithelial cell invasion and persistence in the mouse pulmonary clearance model noted by columns at the right. A closed circle indicates that the result of the assay with the mutant was statistically different from that of wild type. An asterisk indicates that the assay was not possible because the mutant did not reliably grow in the conditions of the assay.</p>