Escherichia coli is one of a few organisms with a well characterized and complete metabolic model for lipoic acid metabolism. In this thesis I make discoveries through analysis of the diversity of lipoic acid metabolic genes in other organisms. By examining the distribution and phylogeny of the lipoate ligase protein family, I and others have found gaps and inconsistencies in our knowledge of lipoic acid metabolic pathways. I examine select proteins through heterologous expression in E. coli, allowing complementation studies and biochemical analysis. This enables prediction of lipoic acid metabolism in various organisms and reveals novel pathways and enzymology
