SUMMARY (UNCHANGED) A fundamental feature of a living system is its integrated network of biochemical pathways that respond to endogenous and environmental stresses. In humans, there is a strong connection between metabolic network dysfunction and disease. Metabolic strategies are conserved across biology, and insights obtained from model organisms provide the means to advance our understanding of general metabolic paradigms, which can often be extrapolated to higher organisms including humans. The long-term goal of the PI's research is to understand the robustness and redundancy of the metabolic network, and to define metabolic components and the processes they participate in. Knowledge of metabolic processes and a mechanistic understanding of the function of unknown proteins is critical to efforts aimed at treating metabolic diseases, and to efforts targeting metabolism for rational drug design, synthetic biology, microbiome research, etc. The goal of the work proposed herein is to advance our understanding of the metabolic stress caused by the 2-aminoacrylate, an obligate intermediate in central metabolic reactions, and the protein that controls it, RidA. Further, this study focuses on the highly conserved Rid protein family, of which RidA is the founding member. In the current proposal we will: i) describe additional, distinct mechanisms that have evolved to deal with similar stress; ii) explore the breadth of 2-aminoacrylate stress and how different organisms handle it, and iii) define the molecular mechanism and cellular role of additional Rid proteins. The goals of this proposal will be accomplished through a combination of chemical, biochemical, molecular genetic, bioinformatics and global approaches. The work here is motivated by our desire to understand the metabolic stress generated by the production of reactive metabolites during growth, how it can damage cellular components if it is not neutralized, and discovering the role of additional members of the broadly conserved protein family that includes RidA.