This contract shall establish large scale, coordinated Systems Biology Programs that utilize a combination of computational and experimental methodologies to analyze, identify, quantify, model and predict the overall dynamics of the network of cellular molecular components of microbial organisms and their interactions with the host cells. These experimental data shall be integrated into other publicly accessible ?-omics? datasets, such as those retrieved from the genomic resources established by the NIAID-supported genomic research programs, to develop and/or validate computational models of the molecular interaction networks involved in biological processes. The resources generated by the System Biology Program shall be made publicly available and easily accessible to the scientific community through public data, software and reagent repositories and through web portals. The ultimate goal of the Systems Biology Program is to enhance knowledge of the overall complexity of the biological, biochemical and biophysical molecular processes in microbial organisms and host cells which may lead to the initiation and progression of infectious diseases.