We will use state-of-the-art, quantitative mass spectrometry-based proteomics to define membership of protein complexes in wild-type and mutant Mtb strains under a variety of growth and perturbational conditions. Systematic and unbiased definifion of the membership of key protein complexes, and the changes in that membership under a variety of growth and perturbaional condtions, will provide critical insights into the biological function of genes important for growth and survival of Mtb. By integrating results of proteomics, metablomics and transcriptomic analyses, a comprehensive picture of the interactions and expression programs critical for growth and survival of the organism should emerge. We will also use state-of-the-art, quantitative global proteomics to profile auxotrophic strains of Mtb to understand the roles of genes encoding proteins and non-coding RNAs of unknown function in M. tuberculosis. We will choose condtions/time points just before changes in growth occur to minimize the possibility that changes in protein abundance are a consequence of changes in growth and survival but, instead, are directly attributable to the mutation. Both wild type and mutant bacteria strains will be analyzed by comparative quantitative proteomic analysis. We anticipate that we will find several different types of changes. We will correlate changes with observations from other experiments across the consortium.