Pasteurella multocida gene expression in response to iron limitation

Pasteurella multocida is the causative agent of a,vide range of diseases in avian and mammalian hosts. Gene expression in response to low iron conditi ons was analyzed in P. multocida using whole-genome microarrays. The analys is shows that the expression of genes involved in energy metabolism and ele ctron transport generally decreased 2.1- to 6-fold while that of genes used for iron binding and transport increased 2.1- to 7.7-fold in P. multocida during the first 2 h of growth under iron-limiting conditions compared with controls. Notably, 27% of the genes with significantly altered expression had no known function, illustrating the limitations of using publicly avail able databases to identify genes involved in microbial metabolism and patho genesis. Taken together, the results of our investigations demonstrate the utility of whole-genome microarray analyses for the identification of genes with altered expression profiles during varying growth conditions and prov ide a framework for the detailed analysis of the molecular mechanisms of ir on acquisition and metabolism in P. multocida and other gram-negative bacte ria.